1 minute read
combustion air inlet
from CLAAS Webasto Water heater Thermo Pro 90 Thermo Pro 90 HDD Service Instructions Manual -PDF DOWNLOAD
2 General description
The water heater has been designed for installation in commercial vehicles. Depending on equipment, the ADR function is provided for the 12 V and 24 V variant.
Parking heating
In parking heating mode, the water heater works together with the vehicle's heating system for
• cab and engine preheating, • use of residual heat from the vehicle engine.
The water heater works independently of the vehicle engine and is integrated in the cooling system, the fuel system and the electrical system of the vehicle.
Auxiliary heating
The water heater works during engine operation and provides thermal assistance to the cooling system. The water heater is integrated in the cooling system, the fuel system and the electrical system of the vehicle.
When the engine is switched off, the water heater is automatically switched off and fuel supply is interrupted within 5 seconds.
The heater operates fully automatically, controlled by the coolant temperature.
The burner output is controlled within the limits between 1.8 and 7.6 kW depending on the deviation of the current coolant temperature from the setpoint at the coolant temperature sensor. The heater switches off burner operation automatically (pause) when the setpoint is exceeded and switches it back on automatically when the temperature drops below the setpoint. Actuation of the water heater with an external regulator (e.g. room thermostat) is not permitted.
The Thermo Pro 90 heater mainly consists of the following components: – Combustion air fan – Heat exchanger – Burner unit – Coolant pump
The following control and monitoring components are integrated in the heater: – Control unit – Exhaust gas temperature sensor – Glow plug – Coolant temperature sensor – Overheating protection
The burner motor speed is monitored by a Hall sensor integrated in the control unit. Operation with a remote control unit is therefore not possible.
The fuel is supplied externally by a fuel pump which is connected to the vehicle fuel system.
1 2 3 4
12 5 6
10
11 7 8 9
1 combustion air fan 2 fuel connection 3 coolant outlet 4 coolant temperature sensor 5 heat exchanger 6 overheating protection 7 exhaust gas temperature sensor 8 outlet, exhaust gas 9 combustion air inlet 10 U4840 coolant pump 11 coolant inlet
