Virtuoso Functional Specification

Functional Specification

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FUNCTIONAL SPECIFICATION FOR VAPAC VIRTUOSO STEAM HUMIDIFIER CONTROLLER AND ASSOCIATED CONTROLS

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The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.

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Functional Specification

D301531 4 23.01.2024 2 of 41 Dean Italiano

REVISION HISTORY REV

APPROVED BY

REVISION DATE

DESCRIPTION OF CHANGE

AUTHOR

0

D Italiano

10.05.2023

Creation of Document

K D Harper

1

D Italiano

27.07.2023

Modified to suit HS comments from meeting 14.07.2023

K D Harper

2

D Italiano

31.07.2023

Section 1.5 added, and document finalised for issue

K D Harper

16.01.2024

Comments from Ian Vaughan added post software development

K D Harper

23.01.2024

Sections 8 and 9 updated to suit latest software. Modbus register information added to section 3 as applicable

K D Harper

3

4

This document is current on 23/01/2024. Following this date, it will be uncontrolled and should be used for reference purposes only.

The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.

Functional Specification 1.

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Introduction .............................................................................................................................. 5 1.1 Purpose of the Document ................................................................................................... 5 1.2 Project Scope / Required Outcomes .................................................................................... 6 1.3 Related / Associated Documents ......................................................................................... 6 1.4 Project Roles and Responsibilities ....................................................................................... 6 1.5 Project Timecale and Milestones ......................................................................................... 6 1.5.1 Project Timescale .............................................................................................................. 6 1.5.2 Project Plan ....................................................................................................................... 7 1.5.3 Project Updates................................................................................................................. 7

2.

3.

System Overview ....................................................................................................................... 8 2.1

General............................................................................................................................. 8

2.2

Operation – VE and VS Models .......................................................................................... 8

2.3

VE Model Touch Screen Display ......................................................................................... 9

2.4

VE Model Touch Screen Display Output ........................................................................... 10

2.5

VE Model Touch Screen Display Input .............................................................................. 11

2.6

VE Model Touch Screen Languages .................................................................................. 11

2.7

VS Model Temperature Control ....................................................................................... 12

2.8

VR Model Operation and Touch Screen Display................................................................ 12

Functional Specifications.......................................................................................................... 13 3.1 VE Electrode Boiler Model .................................................................................................. 13 3.1.1 Configuration .................................................................................................................. 14 3.1.2 Demand Control .............................................................................................................. 14 3.1.3 Temperature / Humidity Sensor Control .......................................................................... 14 3.1.4. Frost Protection.............................................................................................................. 14 3.1.5 Initial Start Up ................................................................................................................. 15 3.1.6 Cylinder Mode................................................................................................................. 16 3.1.7 Foaming .......................................................................................................................... 18 3.1.8 Fast Foaming Detection ................................................................................................... 18 3.1.9 Slow Foaming Detection .................................................................................................. 18 3.1.10 Flushing Drain Routine................................................................................................... 19 3.1.11 Current Measurements for Electrode Boiler Humidifier .................................................. 19 This document is current on 23/01/2024. Following this date, it will be uncontrolled and should be used for reference purposes only.

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Functional Specification

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3.1.12 Over Riding Safety Contraints ........................................................................................ 19 3.1.13 Manual Control Mode.................................................................................................... 19 3.1.14 Standby Drain................................................................................................................ 20 3.1. 15 Periodic Drain ............................................................................................................... 20 3.1.16 Standby Flush ................................................................................................................ 20 3.1.17 Fault Conditions ............................................................................................................ 20 3.2 VS Steam Room Model ....................................................................................................... 22 3.3 VR Resistance Heater Model ............................................................................................... 23 3.3.1 Configuration .................................................................................................................. 23 3.3.2 Demand Control .............................................................................................................. 23 3.3.3 Sensing Head Control ...................................................................................................... 24 3.3.4 Initial Start Up ................................................................................................................. 24 3.3.5 Boiling / Concentration Phase .......................................................................................... 24 3.3.6 De-Concentration Phase .................................................................................................. 24 3.3.7 Standby Drain ................................................................................................................. 25 3.3.8 Manual Control Mode ..................................................................................................... 25 3.3.9 Periodic Drain ................................................................................................................. 25 3.3.10 Periodic Flush ................................................................................................................ 25 3.3.11 Fault Conditions ............................................................................................................ 25 3.4 Output to BMS of Caution Alarm ........................................................................................ 27 3.5 Master / Drone Systems ..................................................................................................... 28 3.6 Touch Screen Display Inputs ............................................................................................... 29 3.7 Touch Screen Display Outputs ............................................................................................ 30 4.

Other Requirements ................................................................................................................ 31

5.

Abbreviations .......................................................................................................................... 32

6.

Table 1 - VE Model SSR Duty Cycle............................................................................................ 33

7.

Table 2 - VR Model SSR Duty Cycle ........................................................................................... 34

8.

Table 3 - Touch Screen Display Inputs ....................................................................................... 35

9.

Table 4 - Touch Screen Display Outputs .................................................................................... 37

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The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.

Functional Specification

1.0

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Introduction

Vapac, a part of the Nortek Global HVAC group, has recently designed the Vapac Virtuoso range of steam humidifiers. The range at present includes:•

Various sizes of electrode boiler steam humidifiers (VExx-1/3P) with a fascia mounted 5” colour touchscreen for user interface giving operator input and humidifier status indication designed for proportional control via either an external 0-10V DC control signal or a 24V DC temperature / humidity sensor (provided by the installer).

•

One size of steam room humidifier (VS18-3P) designed for proportional control via a temperature sensor located within the steam room (supplied loose with the humidifier).

The following outcomes are required under the scope of this document:•

A fully integrated PCB controller, suitable for use across the entire Vapac Virtuoso range, complete with the necessary associated control philosophy and functionality to provide full operational and safety control of the humidifier, along with the required input and output to the colour touchscreen and input and output to the register, being certified to the applicable EMC, UKCA (UK), CE (EU), UL (US) and CSA (Canada) standards and requirements.

•

Identification and remedy / implementation of any shortfalls within this and the associated documents listed in section 1.3 to ensure the full operational and safety control of the humidifier range.

•

At some stage in the future, a resistance steam humidifier (VRxx-1/3P), in various sizes, will be added to the range. The controller and control philosophy and functionality MUST be designed to cover that model when it is eventually added.

1.1

Purpose of the Document

This Functional Specification Document has been produced to provide detailed information on how the system solution will function and provide the requested behaviour. This document is created based on highlevel requirements identified later in this document and associated documents listed below. Included in this document are the detailed functional requirements including use philosophy, system inputs and outputs, process flows, diagrams, and mock ups.

This document is current on 23/01/2024. Following this date, it will be uncontrolled and should be used for reference purposes only.

The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.

Functional Specification 1.2

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Project Scope / Required Outcomes

The design, production, implementation, testing, certification to EMC, UKCA (UK), CE (EU), UL (US) and CSA (Canada) standards and requirements and full integration into the humidifier range of a PCB controller with associated control function to:-

1.3

•

Provide full operational and safety control for the humidifier when provided with various control signal inputs

•

To manage and retain, even in the event of power failure, the registers and inputs / outputs detailed within this document and the associated documents listed in section 1.3 below.

•

To manage and retain, even in the event of power failure, the caution and critical alarms (and their history) detailed within this document and the associated documents listed in section 1.3 below.

•

Accept user input from and provide status indication to the humidifier colour touchscreen (not steam room VS model).

•

Provide Modbus and BACNet interfaces for BMS control and networking of more than one humidifier.

Related / Associated Documents

Document Number N/A N/A N/A

1.4

Project Roles and Responsibilities

Name Dean Italiano Andy Field Ian Vaughan Alex Wronowski

1.5

Document Title Software logic R6A Display Register AKO temperature controller data sheet (VS model only)

Position Innovation Manager Export and Vapac Sales Manager Engineering Team Leader Technical Advisor

Contact Email dean.italiano@nortek.com andrew.field@nortek.com ian.vaughan@nortek.com alex.wronowski@nortek.com

Project Timescale and Milestones

1.5.1 Project Timescale The required time scale for a fully operational PCB controller and associated control philosophy / functionality is 90 days. This is from commencement of the development on day 1 to stock on the shelf ready for production on day 90.

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Functional Specification

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1.5.2 Project Plan A Project Plan is to be shared with Nortek on Day 5 of the project. This will include milestone dates for:1. Delivery of First prototype for comment and testing 2. Delivery of Final product for comment and testing

1.5.3 Project Updates Regular progress updates will be required throughout the project. The expectations for this are:1. Supplier to provide a weekly progress update via email by close of play on Thursday each week. This is to be distributed to Ian Vaughan and Dean Italiano 2. Week 3 - Teams call organised by Nortek for the end of week 3 for a check in, and a review of the Project Plan 3. Week 6 – “Face to face” meeting to demonstrate the products performance.

4. Weeks 9 to 13 – Teams call organised by Nortek for the end of each week from 9 to 13 for a check in, and a review of the Project Plan

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Functional Specification

2.0

System Overview

2.1

General

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Virtuoso is the latest generation of steam humidifier, designed for both comfort (±10% rh) and close control (±5% rh) applications, with the range encompassing the following models at present:Electrode Boiler Models Electrical Supply

Max Power Rating (kW)

FLC per Cylinder (A)

Fuse rating per cylinder (A)

230

1 phase

3.78

19.5

32

1 1

230 400

1 phase 3 phase

6.76 6.79

35.5 20.5

63 32

18 30

1 1

400 400

3 phase 3 phase

13.48 22.38

23.5 39.0

32 50

45 60 90

1 2 2

400 400 400

3 phase 2 x 3 phase 2 x 3 phase

33.85 2 x 44.81 2 x 67.50

59.0 2 x 36.5 2 x 55.0

80 2 x 50 2 x 80

FLC per Cylinder (A)

Fuse rating per cylinder (A)

Model

Steam Output (kg/hr)

No. of Steam Cylinders

Voltage (V)

VE05-1P

5

1

VE09-1P VE09-3P

9 9

VE18-3P VE30-3P VE45-3P VE60-3P VE90-3P

Steam Room Models Model

Steam Output (kg/hr)

No. of Steam Cylinders

Voltage (V)

Electrical Supply

Max Power Rating (kW)

VS18-3P

18

1

400

3 phase

13.48

23.5

32

Electrical Supply

Max Power Rating (kW)

FLC per Cylinder (A)

Fuse rating per cylinder (A)

Resistance Heater Models Model

Steam Output (kg/hr)

No. of Steam Cylinders

Voltage (V)

To be introduced at a later date

All models have been designed to operate with an intelligent combination of feeding, boiling, and draining to operate efficiently and minimise wastage of both water and energy.

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Functional Specification

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All VE models are of the electrode boiler type, with a colour touchscreen for user interface (operator input and system status output) and an I/O/II (on / off / drain) switch mounted on the fascia of the humidifier.

The units are designed to accept control inputs from either an external 0-10V DC control signal or a 24V DC temperature / humidity sensor (note that temperature is purely an output reading and not an operating function).

The VS model is again of the electrode boiler type with an I/O/II (on / off / drain) switch mounted on the fascia of the humidifier. It does not have a colour touchscreen. The unit is designed for temperature control from a fascia mounted AKO temperature controller with an associated temperature sensor located in the steam room.

The future VR models will be of the resistance heater type, with a colour touchscreen for user interface (operator input and system status output) and an I/O/II (on / off / drain) switch mounted on the fascia of the humidifier. The units are designed to accept control inputs from either an external 0-10V DC control signal or a 24V DC temperature / humidity sensor (note that temperature is purely an output reading and not an operating function).

2.2

Operation – VE and VS Models

The humidifier has been designed for operation in the following manner:•

With the I/O/II switch in the “O” (Off) position, the humidifier will be isolated and held off / prevented from operating.

•

With the I/O/II switch in the "I" (Run) position, whenever steam is required by a control input, the electrodes will be supplied with voltage via the main SSR. Simultaneously, the water inlet valve will open, and water will enter the steam cylinder.

•

As soon as the electrodes come into contact with the water, current will begin to flow between the electrodes, boiling the water, in turn producing steam. As more of the electrode surface area is exposed to (conductive) water, the higher the current consumption will become and thus the greater the steam production.

•

The water inlet valve will close when the cylinder conductivity is measured at approximately ¾ full and when higher currents are reached the unit will do a small duty drain to drain concentrated water and a fill will then be required.

•

If the steam generation decreases below a certain percentage of the required capacity, due to the lowering of the water level (e.g., because of the evaporation process or drainage), the water inlet valve will open until the required capacity is available again. Water will be added in stages, initially filling to 50% to start the boil process, then added to.

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Functional Specification

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•

If the required steam capacity is lower than the actual output, the water inlet valve will be closed until the desired capacity is achieved by the lowering of the water level (evaporation process).

•

A cylinder full pin, provided in the steam cylinder, will detect when the cylinder water level is at the maximum. When the sensor comes into contact with water, the water inlet valve will close after a short delay.

•

The drain will operate to remove excess water. If this is indicated three times in an XX time period, the unit will completely drain. If repeated, the unit will stop operating.

•

As a result of the evaporation and refill process, the conductivity of the water will increase due to an escalating mineral concentration. Eventually, an inadmissibly high current consumption will take place if this concentration process were permitted to continue. To prevent this concentration from reaching a value unsuitably high for the operation, a quantity of water will be periodically drained from the cylinder and replaced by fresh water. After a number of operations, the cylinder will be fully drained, and the unit will restart based on the concentration.

•

When starting with an empty cylinder, the Vapac controller will switch in the SSR and feed water until the water level reaches the electrodes and current starts to flow.

•

Thereafter, the system will continuously monitor and control the cylinder conductivity by adjusting the amount of water drained from and fed into the cylinder in the manner described earlier.

•

The controller will be designed to adjust the feed and drain to keep the unit operating in the face of changing water quality in the cylinder and changing electrode condition even if, in an adverse operational circumstance, this results in some reduction in output while the situation exists.

•

Additionally, the control system will be designed to prevent the onset of foaming; introducing corrective drainage to keep the unit working.

•

With the I/O/II switch pressed and held in the “II” (Drain) position, the drain pump will be operated until the switch is released.

The control philosophy / functionality required to achieve the operation discussed above is fully described in section 3 following.

2.3

VE Model Touch Screen Display

The touch screen display is a 5” Colour TFT LCD screen, 800 x 480 pixel resolution with capacitive touch sensing giving a user interface. The various output and input screens described above have already been designed and programmed however, an interface between the touch screen and the PCB controller and associated control functions MUST BE provided under this scope to give the full input and output functionality of the screen as described within the Screen Logic document and this document.

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Functional Specification 2.4

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VE Model Touch Screen Display Output

The touch screen is required to provide the following status indications (to be provided via the controller and associated control functionality):With power to the unit and the I/O/II screen in the "O" (Off) position, the touch screen display panel will show the STANDBY screen.

STANDBY is part of the normal operation of the unit - it is ready for operation.

With power to the unit and the I/O/II switch in the "I" (Run) position, the touch screen display panel will provide status indication of the following:•

STANDBY

•

STEAMING

•

FEEDING

•

DRAINING

•

SERVICE DUE

•

CAUTION ALARM

•

CRITICAL ALARM

STEAMING is part of the normal operation of the unit - current is being supplied to the electrodes and steam is being produced.

FEEDING is part of the normal operation of the unit - the feed valve is opened to add water to the cylinder until the electrode current reaches its target.

DRAINING is part of the normal operation of the unit - the drain pump is run for a preset time by the controller. A default drain occurs after a set number of feed / boil cycles.

An override drain occurs if the electrode current approaches its high limit and stops once the electrode current drops below the cylinder maximum operating current.

SERVICE DUE is part of the normal operation of the unit - when this screen shows, it is an indication to the end user that a service is due, and a service engineer should be called out.

CAUTION ALARM is initiated by one of the following conditions; if any of them occurs, the unit will continue to operate:•

Cylinder low output fault 1

•

Cylinder low output fault 2

•

Feed valve fault

•

Drain fault

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CRITICAL ALARM is raised if the current consumption increases above a preset maximum; if this occurs, the unit will be prevented from operating.

The various screens are fully described within the Screen Logic document which MUST be read in conjunction with this document.

The various alarm conditions MUST be reset via the touch screen. A history log should be held within the system for all alarm conditions (caution and critical).

A pair of terminals (13 and 14) have been provided to allow connection of safety interlocks such as an emergency shut down button or a fire alarm interface / fire shut down facility. Other control interlocks such as a fan interlock, airflow switch, high limit hygrostat or any combination of them may also be connected in series to these terminals. When these terminals are used, the home screen MUST indicate the status of the circuit i.e., Normal or External Interlock Operated.

2.5

VE Model Touch Screen Display Input

The touch screen is required to provide the following user inputs:•

Factory setup / reset

•

Initial start-up including language selection

•

Normal operation with status display for single and double cylinder models

•

Commissioning mode

•

Service mode

•

Advanced mode

The various screens are fully described within the Screen Logic document which MUST be read in conjunction with this document.

2.6

VE Model Touch Screen Languages

The touch screen display is required to provide the following languages (although this list may be added to at a later date):-

1.

English

2.

French

3.

Dutch

4.

German

5.

Spanish

6.

Polish

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The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.

Functional Specification 2.7

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VS Model Temperature Control

The VS Model has been designed for proportional control via a fascia mounted AKO temperature controller and room temperature sensor supplied with the unit and remotely mounted within the steam room it is serving. The VS Model DOES NOT have a touch screen.

The PCB controller and associated control functions MUST BE provided under this scope to give the required steam output to suit the desired steam room temperature set at the sensor.

Because there is no touch screen, the VS Model is unable to provide external indication of a caution or critical fault condition. The controller for the VS Model MUST provide indication for the various fault conditions (see section 3.1.17).

2.8

VR Model Operation and Touch Screen Display

As discussed in sections 1.0 and 2.1 previously, resistive heater humidifiers (VR) will be added to the Virtuoso Range. The operational specification and control requirements for the VR model is detailed in section 3.3 following. It is envisaged at present that the touch screen display will provide similar inputs, outputs, and functionality as that for the VE electrode boiler model.

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Functional Specification

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3.0

Operating Specification / Control Requirement

3.1

VE Electrode Boiler Model

3.1.1

Configuration

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Every time the unit is powered up, the configuration properties are to be set. There needs to be some way of configuring the unit to set the following information:• • • • •

3.1.2

Required output (kg/h) Voltage applied across the electrodes / the number of power electrodes and the number of times the electrode cable is passed through the current sensing transformer The number of cylinders fitted (1 or 2 as scheduled in section 2.1) All the above are required to calculate the maximum operating current “MOC”.

The control signal type.

Demand Control

The required “COC” will always be equal to the “MOC”, and the SSR switch supply will be modified to suit the demand signal in accordance with Table 1 at the rear of this document. The demand threshold for the units is 8%.

3.1.3

Temperature / Humidity Sensor Control

When the control input is provided by a temperature / humidity sensor, the Analogue Input used for the demand signal is to become a proportional signal representing 0 to 100% RH; this should be compared with the required “setpoint”, and a suitable demand calculated using a PID loop to enable the required control condition to be met. This will require the ability to set / adjust the set point and to “Offset” the RH reading to align with other site equipment etc. There must also be the ability to adjust the proportional or integral response times when the unit is controlled by a sensor or BMS. When the unit is controlled by a sensor or BMS, the Humidity Setpoint should not be available as a screen output.

“Control input type” can be set from the touchscreen via select input type screen and also can be accessed via modbus (register 17 R/O)

3.1.4

Frost Protection

When enabled, should the sensed temperature fall below a preset minimum, the master cylinder will be operated to produce steam at a pre-determined demand level and thus overcome any potential frost problems. Typically, at 5°C sensed temperature, the humidifier will run at 20% capacity. Frost demand will be fully adjustable between 0 and 50% (usually set to 20%).

“Frost Protection Setpoint” is accessed from the touchscreen via the Advanced Mode page 6 and also can be accessed via Modbus (register 48 R/W)

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Functional Specification

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“Frost Protection Output” is accessed via Modbus (register 49 R/W) and also from the touchscreen via the Advanced Mode page 6.

3.1.5

Initial Start Up

When the unit first starts up, there will be no water in the cylinder and therefore no current flowing through the electrodes and there will be no current input to the controller.

1. The controller will calculate the “Feed to” value of current – Initially this will be 50% “COC” (See “Demand Control” above).

2. Water will enter the cylinder. When the water reaches the bottom of the electrodes, current begins to flow and the current input to the board will begin to be measured – this “Instantaneous Actual Current” (“IAC”) is to be continually monitored.

3. As the water level increases, the current flow will increase due to the greater area of electrode immersion and as the water heats up (owing to the current flowing through its resistance) its conductivity will also increase giving an even greater rate of current increase.

4. This will continue until either of the following happens:a. The “IAC” is =/> than the Initial “Feed to” level. b. Water reaches the “Cylinder Full Pin”.

When either of these occur, the feed valve will de-energise.

Condition a: The “Boil To” level is set to an initial level of 90% of the latest “IAC”.

The “IAC” is compared with the “Boil to Level” and if it is > 112% of the “Boil to Level” the “Boil to Level” is adjusted to 90% of the “IAC”.

It continues in this way, until either of the following occur:1. The “IAC” peaks and then falls until it reaches the “Boil to” level – at which point the “Feed to level” is adjusted to 110% of the “IAC” (but limited to “COC”. The feed valve energises, and the cycle is repeated using the new “Feed to” level.

2. “IAC” = “COC” – at which time the “Feed to” level remains at this level.

3. Water reaches the “Cylinder Full Pin”.

Condition b: If at any time the water level reaches the “Cylinder Full Pin”, the feed valve will be closed, and the above sequence is “stalled” until the water has boiled away sufficiently for the water level to drop clear of the full pin – at which point it will continue from where it was in the sequence.

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Functional Specification 3.1.6

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Cylinder Mode

During the Operational cycle of the unit, the cylinder will go into a number of different stages or “Modes”:When the unit initially goes “on-line” and the “IAC” is less than the “COC”, the cylinder will be in “Start-Up Mode”. In this mode, the pulsing to the SSR’s will be modified to shorten the start-up time. It achieves this by implementing an automatic boost to the SSR pulsing.

The SSR is proportionally controlled according to the difference between the “IAC” and the required “COC”.

Example - The unit has a demand for 60% duty, but the “IAC” is only 60% of the “COC” so instead of pulsing the SSR on for 480 mS and off for 520 mS, they are pulsed on for (480*(100/60)) mS (or on for 800 mS and off for 200 mS - the same as if the unit had a 100% demand requirement obviously if the requirement had been any higher or if the “IAC” was even less then the SSRs could not be pulsed any more than this and so becomes the upper limit for this boost).

Once the “IAC” has reached the “COC” the start-up phase is complete, and the unit moves to it next phase.

During a “Default Drain” the SSR is de-energised (to avoid the chance of any “Earth Leakage” issues. The length of the “Default Drain” is set initially by the “Configuration Properties” if on completion of the “Default Drain Event” and the SSR is re-energised the “IAC” has not fallen sufficiently (</= 70 % “COC”) another “Default Drain” is performed, and the “Default Drain Period” is set at 1.5 times the previous setting.

This new value will then be stored and used subsequently for future “Default Drains”.

Currently the software undertakes to do a fixed number of “Boil/Feed Events” (4 when “Water Economy” is “Enabled” and 3 when “Water Economy” is “Not Enabled”) before a drain event takes place. While this does reduce both the amount of water and the amount of energy which has heated this wastewater, it is certainly not optimising the amount of savings made. To achieve this, we need to be able to automatically adjust the number of feed/boil events according to the water quality supplied.

There are several “Indicators” which can be used to give the controller this “Intelligence”. As most “issues” are caused by “high current density”. Too much current flowing through too small a cross sectional area of water which occurs when the water becomes over concentrated, and the cylinder water level gets too low.

The issues seen are Foaming: Arcing and Electrode Erosion.

•

Over concentration of the water means that very little evaporation needs to occur before the current has dropped sufficiently to trigger a feed event and as the boil off rate is constant (for a constant demand) the time taken to boil down from the “Feed To” level to the “Boil To” level reduces as does the feed time as less water is required to top up the evaporated quantity Therefore the “Boil/Feed Time” reduces as the water in the cylinder becomes more concentrated. It must be noted that the rate of “Boil Off” will depend on the demand present i.e., the “Boil Off” rate will be half that of a unit running with a 100% “Demand”, when it is running with a “Demand” of 50%. Half the rate of boil off means that it will take twice as long to boil down.

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Functional Specification

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•

There is a finite time for the controller to react to the electrode current being equal to the “Feed To” level and to then switch the feed valve off. This time will remain “constant” irrespective of the concentration of the water in the cylinder and therefore the amount of “excess” water entering the cylinder during this time will also be constant. As the water becomes more concentrated, this “excess water volume” will become a larger proportion of the water remaining in the cylinder after the current reaches the required level and will therefore have a greater effect on it. The “Current Overswing” will therefore become larger as the water in the cylinder becomes more concentrated.

•

Following a “Default Drain” if the water level is below the bottom of the electrodes when the SSR is energised so that no current flows the software should instigate a “Concentration Total Drain” as the water is considered to be “over concentrated” on completion of this operating data is wiped clean and the unit starts from with the beginning, in “Start Up Mode”. There may still be a small leakage current where current tracks through the wet scale.

Initially the number of “Feed Boil Events” should be set to “X” (where initially X = 3) and measure and store both the following:1. The “initial” average “Boil/Feed Time” for each of each of the 3 off “Feed/Boil Events”. The time between the feed valve switching off, when the “IAC” reaches the “COC” as modified by the average demand applied as described above.

2. The average “Peak IAC” for each of the “X” number of “Feed/Boil Events”.

After this “Concentration stage” the controller should perform a “Default Drain”. The duration of which is set from the configuration properties.

If the water level falls below the electrodes so that there is no current drawn when the SSRs re-energise, the number of “Boil/Feed Events” should be decremented by one and the process above repeated, if not the process is repeated without decrementing the number of “Boil/Feed Events” to “X-1”.

On completion of the second & subsequent concentration cycles, the “current” average “Boil/Feed Time” is compared to the stored “Initial” “Boil/Feed Time” – If the change is <+y% and the “current average” “Peak IAC” is <xxx% of the “COC” then increment the number of “Feed/Boil Events” to “X+1” - If either of the two above conditions is “False”, then the number of “Feed/Boil Events” X remains unchanged.

Again, on completion of each concentration cycle the controller instigates a “Default Drain” and the cycle repeats.

If at any time the unit detects “Foaming” the corrective action as described below should be taken, and the number of “Feed/Boil Events” should be updated to “X-1”.

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Functional Specification 3.1.7

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Foaming

Foaming is where the mineral content of the concentrated water in the cylinder is such that when the bubbles of steam burst, there is a sufficiently strong mineral coating to maintain the shape and support further shapes. As this “shell” is conductive if there is sufficient foam to connect from the electrodes to the full pin, a false cylinder full condition will exist preventing further water to enter the cylinder. There are two possible forms of foaming: •

•

3.1.8

Fast Foaming – where the water reaches the “foaming threshold” and begins to foam violently, causing the current to drop suddenly and the false cylinder full signal prevents the feed valve from operating and replenishing water in the cylinder.

Slow Foaming – where during start up the water begins to foam gently and so the cylinder spends large periods of time drawing low currents and takes an extraordinary long time to start producing steam

Fast Foaming Detection

The following sequences may indicate the presence of “Foaming” and on detection, a “Concentration Total

Drain” should be performed, and all “Operational Data” cleared. On completion, the unit should enter the “Start-Up Mode” and generate new “Operating Data”.

•

•

If during the “Start-Up Mode”, water reaches the “Cylinder Full Pin” before the “COC” is reached and the “IAC” at subsequent “Cylinder Full” events falls to <95% of the max “IAC” following the initial “Cylinder Full” event.

During normal run or during the concentration phase having reached the “COC” the water hits the “Cylinder Full Pin” after being clear of the pin. That is that even though the mineral concentration in the cylinder is higher, the water appears to have filled higher than it previously had to reach the “COC”.

If either of these conditions occur, then a “Concentration Total Drain” should be performed – Additionally the number of Feed/Boil events should be re-adjusted to “X-1”.

3.1.9

Slow Foaming Detection

The “Slow Foaming Time” should initially be set to 60 minutes.

1. When the cylinder full pin is reached a timer records the length of time that the circuit is made, if it exceeds the “Cylinder Full Time” then: 2. Undertake a “Default Drain” but on completion, do not refill.

3. Check to see if the full condition returns within 20 Seconds. a. If it does not, reset the “Slow Foaming Time” to 1.5 x previous value. Go To 1 above. b. Else undertake 2 x “Default Drains” but on completion do not refill, check if the full condition returns within 20 seconds. i. If it does not, reset the “Slow Foaming Time” to 1.5 x previous value. Go To 1 above. ii. Else “Flushing Drain Routine” the number of Feed/Boil events should be re-adjusted to “X-1”.

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Functional Specification

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3.1.10 Flushing Drain Routine 1.

2.

3.

4.

Perform a “Total Drain”.

Fill to Cylinder Full.

Perform another “Total Drain”.

Return

3.1.11 Current Measurements for Electrode Boiler Humidifier The controller will measure and report the RMS current on analogue inputs 2 and 3. The specification for these two inputs is 0.1V per Amp (5V = 50A) This RMS current is either derived from the peak or the average, with the following algorithm being applied:if (Peak RMS > Average RMS + 10%) use Peak RMS else use Average RMS The controller should provide a calculation of the RMS current from an average of readings over a 500 mS period. Readings should only be taken when the SSR is pulsed ON. The controller will monitor the RMS current and provide over current control. Under this scheme the controller will be given an over current value and several consecutive cycles (typically 3 or 6). There will be two pairs (over current value and consecutive cycles) of values, one for analogue input 2 and one for analogue input 3. For each input, the controller will monitor for the RMS value being above the over current value for the specified number of cycles. If this condition occurs, then the controller will turn off the appropriate SSR output and instigate an over current routine.

3.1.12 Over Riding Safety Constraints 1. If at any time the “IAC” reaches 110% of the unit “MOC” the drain pump is enabled until the “IAC” drops back to 100% “MOC”.

2. If the “IAC” reaches 115% of the “MOC” then the SSR is de-energised, and the drain pump switched on (“On” time equal to “Cylinder Full Drain Time” which is set from the initial configuration properties). The SSR is then re-energised, and the “IAC” re-checked - If it remains above the “MOC” the cycle is repeated (max 3 attempts only) if it is still above the “MOC” after this the unit is “Shutdown” and a “High over current” stop alarm generated.

3.1.13 Manual Control Mode There would be a requirement to manually switch the digital outputs independently to enable them to be tested. It should also be possible to set a “Constant Output” for a period. Both the “Demand Level” and “Time Period” should be adjustable and during this time the unit should take this as the true demand and ignore the “Analogue Input (wired) Signal”.

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Functional Specification

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3.1.14 Standby Drain If the unit remains in “Standby” for a period exceeding the “Standby Drain Interval”, the unit will do a “Total Drain” and set a flag (“Cylinder Empty”) to prevent the unit from attempting further “Standby Drains”. The “Cylinder Empty” flag is cleared when the “Feed Valve” is energised. The “Standby Drain Interval” is adjustable (0 – 9999 hours) and by default is set to “72 hours”.

“Standby Drain Interval” is accessed via Modbus only (register 62 R/W).

3.1.15 Periodic Drain It should be possible to set a “Periodic Drain” with an adjustable time period in hours, with 0 being off. The “Periodic Drain” should consist of switching off the SSR and completing a “total drain”; after which the unit should either continue to operate according to the control signal or go to the “Off state” until the operator has intervened in some way depending on the choice made by the operator when setting up the “Periodic Drain”. The “Periodic Drain” is adjustable (0-192 hours) and by default is set to “6 hours”.

“Periodic Drain” is accessed from the touchscreen via the commissioning mode page 1 and also can be accessed via Modbus (register 61 R/W).

3.1.16 Standby Flush Like the “Standby Drain”, but after the unit has completed the “total drain” it should open the “feed valve” for a time equal to the “Max Feed Time”, then carry out another “total drain”. On completion of the “Standby Flush”, the unit should again either continue to operate or go to the “Off State” depending on the choice of the operator when setting up the “Standby Flush”.

3.1.17 Fault Conditions 3.1.17.1

High Over-current Stop

See 3.1.12 over-riding safety conditions

3.1.17.2

Low Output #1

Generated if the Cylinder current fails to reach =/> “X” % of “COC” within “Y” minutes of operation.

X = adjustable 0-80% (Default 80%) Y= adjustable 0-9999 Minutes (Default 30 minutes)

3.1.17.3

Low Output #2

Generated if having reached “COC” cylinder current falls to =/< “X” % of “COC” for a period of “Y” minutes X = adjustable 0-80% (Default 60%) Y= adjustable 0-9999 Minutes (Default 240 minutes)

3.1.17.4

Feed Fault

If the “Feed Valve” remains open for longer than the “Max Fill Time” (set from initial “Configuration Data” without reaching “Cylinder Full”.

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Functional Specification 3.1.17.5

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Drain Fault

Generated if the pump has been running for a period =/> the “Max Drain Time” Or if following a second attempt at a “Total De-Concentration Drain” the “IAC” is still > “Cylinder Empty Current”.

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Functional Specification 3.2

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VS Steam Room Model

The VS Steam Room humidifier is to all intents and purposes the same as the VE Electrode Boiler humidifier but without a touch screen being controlled via a fascia mounted AKO temperature controller and an associated temperature sensor located in the steam room, thus the required overall control philosophy for the VS is very similar to the VE described in section 3.1 previously, however, where section 3.1.3 refers to temperature and humidity sensor control, temperature only control will obviously apply for the VS. The design of the VS unit at present does not have any means to provide external indication of a fault condition. The indication for the various fault conditions (see section 3.1.17) is to be provided by the controller for the VS.

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Functional Specification 3.3

VR Resistance Heater Model

3.3.1

Configuration

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Every time the unit is powered up, the configuration properties are set. There needs to be some way of configuring the unit to set the following information:• • • •

Required Output (kg/h) Voltage applied across the elements / the number of elements.

The number of cylinders fitted (1 / 2) Whether the unit is fitted with SSRs or just operates as on/off (see below).

Initial Configuration Properties: Unit Capacity (kg)

Water Type De-min De-Ion Softened Pot Low Pot Med Pot High

Feed Total Default Pump Fault Drain Drain Pulse Time (s) Time (s) Time (s) Time (s) To be introduced at a later date Service Interval (h) 5000 5000 2500 2500 1000 500

DD Period (min) 2880 1440 30 120 60 20

Drain Fault Time (s)

Stand-by Drain Period (h) 6 6 0 0 0 0

Unlike the VE electrode boiler where the resistance of the path through the water between the electrodes can be varied by adjusting the water level to give a proportional output, the resistive heater elements have a fixed resistance and will always operate at the same output so if there are no SSRs fitted the unit will only provide an “On/Off” output.

3.3.2

Demand Control

Depending on whether the unit is required to operate as LRP or LR will determine how the controller will respond to the control signal:• •

LR, the Unit operates “On/Off” only. The demand threshold for LR units is 20%.

LRP, the SSRs switch supply will be modified to suit the demand signal in accordance with Table 2 at the rear of this document. The demand threshold for LRP units is 20%

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Functional Specification 3.3.3

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Sensing Head Control

When selected, the Analogue Input used for the demand signal becomes a proportional signal representing 0 to 100% RH. This should be compared with the required “setpoint”, and a suitable demand calculated using a PID loop to enable the required control condition to be met. This requires the ability to set / adjust the set point and to “Offset” the RH reading to align with other site equipment etc.

3.3.4

Initial Start Up

When called to operate, the controller looks at the two “float switch” “inputs” to ascertain the water level in the cylinder. Initially there will be no water in the cylinder, so both float switches will be “open”.

The controller therefore opens the “feed valve”, and water starts to flow into the cylinder.

This continues until there is sufficient water in the cylinder to cover the elements and “make” the 1st (lower) float switch.

When this makes, the controller will “energise” the “SSR” output, applying power to the elements. The “feed valve” remains energised and continues to feed water into the cylinder – until the 2nd (top) float switch “makes”, at which time the controller de-energises the feed valve.

Once the water has boiled away sufficiently to clear the “Top Float Switch”, the “Initial Start Up” phase is complete, and the unit enters the “Boiling/Concentration Phase”.

3.3.5

Boiling / Concentration Phase

The controller follows the demand signal (LRP units pulsing the SSRs to generate a “Proportional Output” & LR units working at 100% duty, while the control signal is present - If a proportional signal is applied if it is =/> 20% it will run).

Each time the water evaporates clear of the “Top Float Switch” and the unit is being called for, the controller will energise the “Feed Valve” until it again makes the “Top Float Switch”.

3.3.6

De-Concentration Phase

Depending on the type of water (De-Ionised; Demineralised; Softened; Potable Low; Potable Medium; Potable High) fed to the unit, the unit will stay in the “Boiling Phase” until the “Default Drain interval” (taken from the “Initial Configuration Properties”) has expired. At this time the unit will enter the “Deconcentration Phase”. During this phase every time the unit fills, and the “Top Float Switch” “makes” the unit will perform a short “Pulsed Drain” (the period of the pulse is set by the “Initial Configuration Properties” – the number of these “Pulsed drains” will be equal to the “Integer Value” of the (“Default Drain Time”)/(“Drain Pulse Time”). Once the final “Pulsed Drain” is complete the unit will revert to the “Boiling/Concentration Phase”.

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Functional Specification 3.3.7

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Standby Drain

If the unit remains in “Standby” for a period exceeding the “Standby Drain Interval”, the unit will do a “Total Drain” and set a flag (“Cylinder Empty”) to prevent the unit from attempting further “Standby Drains”. The “Cylinder Empty” flag is cleared when the “Feed Valve” is energised. The “Standby Drain Interval” is only active when De-Ionised or De-Mineralised water is selected. The “Standby Drain Interval” is adjustable (0 – 9999 hours) and by default is set to “72 hours”.

“Standby Drain Interval” is accessed via Modbus only (register 62 R/W).

3.3.8

Manual Control Mode

There would be a requirement to manually switch the digital outputs independently to enable them to be tested. It should also be possible to set a “Constant Output” for a period. Both the “Demand Level” and “Time Period” should be adjustable and during this time the unit should take this as the true demand and ignore the “Analogue Input (wired) Signal”.

3.3.9

Periodic Drain

It should be possible to set a “Periodic Drain” with an adjustable time period in hours, with 0 being off. The “Periodic Drain” should consist of switching off the SSR and completing a “total drain”; after which the unit should either continue to operate according to the control signal or go to the “Off state” until the operator has intervened in some way depending on the choice made by the operator when setting up the “Periodic Drain”. The “Periodic Drain” is adjustable (0-192 hours) and by default is set to “6 hours”.

“Periodic Drain” is accessed via Modbus (register 61 R/W) and also from the touchscreen via the commissioning page.

3.3.10 Standby Flush Like the “Standby Drain”, but after the unit has completed the “total drain” it should open the “feed valve” for a time equal to the “Max Feed Time”, then carry out another “total drain”. On completion of the “Standby Flush”, the unit should again either continue to operate or go to the “Off State” depending on the choice of the operator when setting up the “Standby Flush”.

3.3.11 Fault Conditions 3.3.11.1

High Temperature Alarm

The coil of the SSR is in series with the “Over Temperature Thermostat” so if the cylinder overheats, the stat opens and de-energises the SSR removing power from the elements. Therefore, if the controller calls for the SSR to make, but the controller does not get “Positive Feedback” that the SSR has made (Digital Input not made by “SSR Auxiliary Contact”) the controller will switch the unit to “Standby” and indicate “High Temperature Alarm”.

3.3.11.2

Feed Fault

If the “Feed Valve” remains open for longer than the “Feed Fault Time” (set from initial “Configuration Data” without making “Top Float Switch”.

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Functional Specification 3.3.11.3

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Drain Fault

In the “De-Concentration Phase” during every xth “Pulsed Drain” the “Drain Pump” is held on longer until the “Lower Float Switch” breaks – the instant this happens, the “Drain Pump” is switched off and the “Feed Valve” is “energised”.

3.3.11.4

Float Switch Fault

If the “Top Float Switch” is “made” but the “Lower Float Switch” is not, then there is obviously an “Issue” so the unit will revert to “Shutdown” and a “Float Switch Fault” will be indicated.

3.3.11.5

Service Interval Expired

This is the period that elapses before a service routine is required. The timer that is used to check for this is only active while there is a demand signal. The “Time Period” is initially set from the “Water Type” selected during set-up but can be adjusted “Up/Down” as necessary by the service engineer depending on the findings during a “Service Visit”.

The Initial Service Intervals are as follows:De-Mineralised De-Ionised Softened Potable Low Potable Medium Potable High

5000 hours 5000 hours 2500 hours 2500 hours 1000 hours 500 hours

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Functional Specification 3.4

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Output to BMS of Caution Alarm

As discussed in section 2.4 previously, a CAUTION ALARM is initiated by one of the following conditions; if any of them occurs, the unit will continue to operate:•

Cylinder low output fault 1

•

Cylinder low output fault 2

•

Feed valve fault

•

Drain fault

There needs to be some method of sending an alarm signal output to a Building Management System (BMS) to indicate (1) there is a caution alarm, (2) the type of caution alarm and (3) the unit is still operating.

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Functional Specification 3.5

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Master / Drone Systems

There needs to be some method of assigning several units to operate as a “Single System” where one “Master” unit controls several “Drones” (up to a maximum of >10 cylinders) from a single control signal at the “Master”.

The “Master” unit calculates (Using the algorithm Slave x demand = {(System Demand * No of Cylinders/100 – (x-1)} * 100) which “Drones” are required to switch on and will bring them on as required to achieve the required duty. It will bring them on “one at a time” and will not bring on the next until the first is producing steam (i.e., has completed one Feed/Boil event).

The Master will always be the largest (or equal largest) duty unit and will usually be an LRP (“Proportional”) unit and will modulate its’ own output (up/down) to provide the “Proportional” (Top Up) part of the output.

Although the “Master” unit controls the “On/Off sequencing” of the individual “Drone” units, the “Drone” controller will control the standard unit I.O.

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Functional Specification 3.6

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Touch Screen Display Inputs

The controller and associated control functionality must accept and handle accordingly the inputs from the touch screen display scheduled in table 3 at the rear of this document. All inputs must be stored in nonvolatile memory such that they will be retained and stored if the unit is electrically isolated (i.e., no power to the unit).

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Functional Specification 3.7

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Touch Screen Display Outputs

The controller and associated control functionality must provide the outputs to the touch screen display scheduled in table 4 at the rear of this document. All outputs must be stored in non-volatile memory such that they will be retained and stored if the unit is electrically isolated (i.e., no power to the unit).

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Functional Specification

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4.0 Other Requirements Shortfalls - As stated in the introduction to this functional specification, the controller and associated controls function provider MUST identify and remedy / implement any shortfalls within this and the associated documents so as to ensure the full operational and safety control of the humidifier range.

Timescale - The required time scale for a fully operational PCB controller and associated control philosophy / functionality is 90 days from the placing of an order with the supplier.

Certification – the controller and associated controls must be certified to the applicable EMC, UKCA (UK), CE (EU), UL (US) and CSA (Canada) standards and requirements.

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Functional Specification

5.0 COC IAC MOC P+ PE t WL

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Abbreviations Cylinder Operating Current - Current that needs to be drawn to provide the required steam output.

Instantaneous Actual Current - Actual current being drawn by the cylinder.

Maximum Operating Current of the Electrode Boiler cylinder.

Power uplift to compensate for the reduced output because of cold feed water.

"Pulsed Energy" Electrode Boiler & Resistance Heater Units fitted with SSRs. Time taken for the power uplift to decay back to zero after the feed valve switches off.

"Water Level Control" only used for Electrode Boiler Units not fitted with SSRs.

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Functional Specification

6.0

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Table 1 – VE Model SSR Duty Cycle

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Functional Specification

7.0

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Table 2 – VR Model SSR Duty Cycle

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Functional Specification

8.0

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Table 3 – Touch Screen Display Inputs

Screen

Input / Action

Select Model Select Language Select Voltage

Selection and storage of unit model Selection and storage of language Selection and storage of voltage for single phase models Selection and storage of voltage for three phase models Selection and storage of control input type Selection of Service Mode and access to and storage of associated settings via onscreen PIN keypad access (4112) Selection of Commissioning Mode and access to and storage of associated settings via onscreen PIN keypad access (6787) Selection of Advanced Mode and access to and storage of associated settings via onscreen PIN keypad access (9999) Selection and storage of language Selection and storage of humidity setpoint via onscreen keypad (on/off input only) Selection and storage of control input type Selection and storage of maximum service interval via onscreen keypad.

A “Service Due” flag is to be displayed onscreen once the set value has been exceeded Selection and storage of full drain interval Selection and storage of proportional factor Selection and storage of integral factor Selection and storage of number of feed / boil events Selection and storage of default drain time Selection and storage of maximum feed time Selection and storage of maximum drain time Entry and storage of WiFi SSID Entry and storage of WiFi password Storage of IP address (normally assigned automatically but can be entered manually from this screen) Selection and storage of Modbus baud rate Selection and storage of Modbus node address Pressing onscreen “Fill” button to operate fill valve until button is released Pressing onscreen “Drain” button to operate drain pump until button is released Selection and storage of demand via onscreen keypad Pressing onscreen “Reset” button to reset service interval counter to zero

Select Input Type Select Mode

Commissioning Mode Page 1

Commissioning Mode Page 2 Commissioning Mode Page 3 Commissioning Mode Page 4 Commissioning Mode Page 5 Service Mode Page 1 Service Mode Page 2 Service Mode Page 3 Advanced Mode Page 1 Advanced Mode Page 2

Pressing onscreen “Reset Alarms” button to reset all alarm conditions No inputs from this screen – the display is all outputs as scheduled in table 4 Selection and storage of low output level 1 demand percentage via on screen keypad Selection and storage of low out put level 1 within time via on screen keypad

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The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.

Functional Specification

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Screen

Input / Action

Advanced Mode Page 3 Advanced Mode Page 4 Advanced Mode Page 5 Advanced Mode Page 6 Advanced Mode Page 7

Selection and storage of low output level 1 demand percentage via on screen keypad Selection and storage of low output level 2 within time via onscreen keypad Selection and storage of derate output demand via onscreen keypad

Critical Alarm Screen Caution Alarm Screen

Selection and storage of sensor offset humidity via onscreen keypad Selection and storage of sensor offset temperature via onscreen keypad Selection and storage of frost protection setpoint via onscreen keypad Selection and storage of frost protection output via onscreen keypad Pressing onscreen “Service Settings Reset” button to clear all settings entered via Service Mode Pages 1, 2 and 3 Pressing onscreen “Commissioning Settings Reset” button to clear all settings entered via Service Mode Pages 1, 2 and 3 Pressing onscreen “Advanced Settings Reset” button to clear all settings entered via Advanced Mode Pages 1, 2, 3, 4 and 5 Pressing onscreen “All Settings Reset” button to clear all settings entered via Service Mode, Commissioning Mode, and Advanced Mode Pages Pressing onscreen “Factory Settings” button to clear all stored settings protected by a PIN number (544671) then to return to “Enter Model” screen No inputs from this screen – the display is all outputs as scheduled in table 4 No inputs from this screen – the display is all outputs as scheduled in table 4

This document is current on 23/01/2024. Following this date, it will be uncontrolled and should be used for reference purposes only.

The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.

Functional Specification

9.0

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Table 4 – Touch Screen Display Outputs

Screen

Output / Action

Select Model Select Language

On selection of model, all screens will display the model.

On selection of language, the screen display for all screens will change to that language until changed via input from Select Mode page On initial start-up, this screen will display until the controller has booted up and is fully ready for operation No outputs from this screen – the display is all inputs as scheduled in table 3

Starting Up Please Wait…

Select Voltage Single Phase Select Voltage Three Phase Select Input Type Standby Home Screen Single Cylinder Units

Home Screen Double Cylinder Units

No outputs from this screen – the display is all inputs as scheduled in table 3 No outputs from this screen – the display is all inputs as scheduled in table 3 Display indicates that the humidifier is operational and ready to provide steam when required by the control input. Display indicates “Interlock Open” to show that there is no demand for steam (enable signal) from the selected control input.

Display of unit status – green dot if ok, flashing orange dot plus fault code plus caution alarm screen (see later) if there is a caution alarm condition.

Display indicates Steam Output Demand, value provided by the controller Display indicates Demand, value provided by the controller Display indicates Current, value provided by the controller.

Display indicates Steaming Icon when humidifier is called to produce steam via the control input and controller Display indicates Filling Icon when humidifier is called to fill by the controller Display indicates Draining Icon when humidifier is called to drain by the controller Display indicates live current drawn by the cylinder Display of unit status – green dot if ok, flashing orange dot plus fault code plus caution alarm screen (see later) if there is a caution alarm condition.

Display indicates Steam Output Demand, value provided by the controller Display indicates Demand, value provided by the controller Display indicates Current, value provided by the controller.

Display indicates Steaming Icon for each cylinder when humidifier is called to produce steam via the control input and controller. There are times when either cylinder could be producing steam so the display and the controller must handle each cylinder separately Display indicates Filling Icon when humidifier is called to fill by the controller. There are times when either cylinder could be filling so the display and the controller must handle each cylinder separately Display indicates Draining Icon when humidifier is called to drain by the controller.

There are times when either cylinder could be draining so the display and the controller must handle each cylinder separately Display indicates live current drawn by each cylinder

This document is current on 23/01/2024. Following this date, it will be uncontrolled and should be used for reference purposes only.

The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.

Functional Specification

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Screen

Output / Action

Select Mode

No outputs from this screen – the display is all inputs as scheduled in table 3.

Commissioning Mode Page 1

Display indicates humidity setpoint, taken from the saved value inputted from the commissioning mode page 1 screen only when the control input type selected is on / off input Display indicates input type, taken from the saved value inputted from the commissioning mode page 1 screen or from the initial set up Display indicates maximum service interval, taken from the saved value inputted from the commissioning mode page 1 screen Display indicates full drain interval, taken from the saved value inputted from the commissioning mode page 1 screen Display indicates proportional factor, taken from the saved value inputted from the commissioning mode page 2 screen Display indicates integral factor, taken from the saved value inputted from the commissioning mode page 2 screen Display indicates number of feed / boil events before completing a default drain, taken from the saved value inputted from the commissioning mode page 2 screen Display indicates default drain time, taken from the saved value inputted from the commissioning mode page 2 screen Display indicates maximum feed time, taken from the saved value inputted from the commissioning mode page 3 screen Display indicates maximum drain time, taken from the saved value inputted from the commissioning mode page 3 screen Display indicates the software version Display indicates the touchscreen software version Display indicates the WiFI SSID, taken from the saved value inputted from the commissioning mode page 4 screen Display indicates the WiFI Password, taken from the saved value inputted from the commissioning mode page 4 screen Display indicates the WiFI IP Address, taken from the saved value assigned by the software, although this can be manually inputted from the commissioning mode page 4 screen Display indicates the Modbus node address, taken from the saved value inputted from the commissioning mode page 5 screen Display indicates the Modbus baud rate, taken from the saved value inputted from the commissioning mode page 5 screen Display indicates demand, taken from the saved value inputted from service mode page 1 Display indicates service interval, taken from the saved value inputted from the commissioning mode screen Display indicates use since last service in hours, taken from the value measured and stored by the controller Display indicates unit total power consumption, taken from the value measured and stored by the controller

Commissioning Mode Page 2

Commissioning Mode Page 3

Commissioning Mode Page 4

Commissioning Mode Page 5 Service Mode Page 1 Service Mode Page 2

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The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.

Functional Specification

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Screen

Output / Action

Service Mode Page 3

Display indicates fault description and code (See caution alarm screen overleaf) provided by the controller Caution Alarms:-

Advanced Mode Page 1

Advanced Mode Page 2 Advanced Mode Page 3 Advanced Mode Page 4 Advanced Mode Page 5 Advanced Mode Page 6 Advanced Mode Page 7 Critical Alarm

Critical Alarm:-

Cylinder low output Current consumption rises above preset Feed fault limit Drain fault (See section 3.12 for definition) No voltage to controller (See section 3.17 for definitions) Display indicates incoming power supply based on the values entered on the Select Voltage screens and stored by the controller Display indicates maximum current rating based on the value held for each model and stored by the controller Display indicates maximum power consumption based on the value held for each model and stored by the controller Display indicates steam output based on the value held for each model and stored by the controller. Real time data would be preferable, Display indicates actual steam output demand based on the value held for each model and stored by the controller. Real time data would be preferable.

Display indicates external demand based on the requirement of the control input and measured by the controller Display indicates total hours run based on the value stored by the controller Display indicates demand set from the Set Low Output Level 1 screen and stored by the controller Display indicates within time-based set from the Set Low Output Level 1 screen and stored by the controller Display indicates demand set from the Set Low Output Level 2 screen and stored by the controller Display indicates within time set from the Set Low Output Level 2 screen and stored by the controller Display indicates demand set from the Derate Output screen and stored by the controller Display indicates sensor humidity offset value set from the Derate Output screen and stored by the controller Display indicates sensor temperature offset value set from the Derate Output screen and stored by the controller Display indicates frost protection output set from the saved value inputted from Advanced mode page 6 Display indicates frost protection setpoint set from the saved value inputted from Advanced mode page 6 There are no outputs associated with this screen This screen will be displayed in the event of current consumption rising above preset limit (see section 3.12 for definition)

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The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.

Functional Specification

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Screen

Output / Action

Caution Alarm

This indication will flash intermittently (and display a fault code) with the home screen for both single and double cylinder units in the event of:Single Cylinder Units :Feed valve fault - Fault code 1 - (see section 3.17.4 for definition) Cylinder low output 1 - Fault code 2 - (see section 3.17.2 and 3.17.3 for definition) Cylinder low output 2 - Fault code 4 - (see section 3.17.2 and 3.17.3 for definition) Drain fault - Fault code 8 - (see section 3.17.5 for definition) Double Cylinder Units :Feed valve fault - Fault code 16 - (see section 3.17.4 for definition) Cylinder low output 1 - Fault code 32 - (see section 3.17.2 and 3.17.3 for definition) Cylinder low output 2 - Fault code 64 - (see section 3.17.2 and 3.17.3 for definition) Drain fault - Fault code 128 - (see section 3.17.5 for definition) See section 3.17 for definitions

This document is current on 23/01/2024. Following this date, it will be uncontrolled and should be used for reference purposes only.

The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.

Functional Specification

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NORTEK GLOBAL HVAC (UK) LTD Fens Pool Avenue Brierley Hill West Midlands DY5 1QA United Kingdom Tel +44 (0)1384 489700 Fax +44 (0)1384 489707 vapacsales@nortek.com www.vapac.com

This document is current on 23/01/2024. Following this date, it will be uncontrolled and should be used for reference purposes only.

The current version of this document is maintained by the Nortek Global HVAC UK Technical Author.