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Table of Contents About Thermo King

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The latest advances in climate control technology

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By Steve D. Johnson, Sr.

Ensuring durability

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By Steve D. Johnson, Sr.

Eco-friendliness is a priority for HVAC

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By Steve D. Johnson, Sr.

Preventative maintenance

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By Steve D. Johnson, Sr.

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THERMO KING Thermo King is the world leader in transport temperature control systems for trucks, trailers, buses, rail cars and shipboard containers. Thermo King also manufactures auxiliary power units, which dramatically reduce engine idling. All Thermo King products are backed by a nationwide dealer network, which provides expert factorytrained service and a complete line of genuine and competitive parts. THERMO KING HISTORY It all started on a hot summer day in 1938 and a customer’s need to keep a load of fresh chickens cold while transporting them to market. Joe Numero accepted the challenge, and with the engineering genius of Frederick M. Jones, the two launched Thermo King and began the age of modern transport refrigeration. Ever since that day, Thermo King has been developing customer-focused innovations that deliver efficiency, reliability and safety across the planet. That commitment to innovation continues, helping to grow businesses and improve lives now and into the future. PRODUCT PERFORMANCE Long-term value for your business When your transportation equipment meets the demands of service with reliability and efficiency, it contributes to your profitability. With 75 years in the industry, Thermo King equipment has repeatedly proven its dependability, and our products retain their value longer than any others in the industry.

Built-in savings Better design means a lower cost of ownership. Tough construction, proven reliability and efficiency help you save money on service and maintenance costs. Our sustainable designs pay off with reduced energy consumption, including built-in technology to modulate the engine and maintain temperature. Quality testing in our labs improves product performance, which means fewer breakdowns. With our longer maintenance cycles, you’ll save time and money. Expert service and support When you need support, you’ll get assistance from providers who are trained and certified to specifically service our products. And with the largest service network in North America providing assistance 24 hours a day, you have the support you need anytime, anywhere. Through Thermo Gard™ Service and Maintenance Solutions, you can choose the service program that best fits your business needs. Take advantage of repair authorization options, centralized billing, extended warranty options, and service at any of our over 200 factory-authorized service centers nationwide.

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The latest advances in climate control technology By Steve D. Johnson, Sr. What are the latest advances in climate control technology? It sounds like a relatively easy question to answer, right? When the question was asked of me recently, however, my thoughts went immediately to “what’s trending in the transit bus industry?” Ask any transit professional today and most will mention “energy efficiency and sustainability” in one context or another. So what does that mean and how is it related to HVAC technology? Consider this statement: “I want to become more environmentally conscious by reducing my carbon footprint and I am looking for new technologies that help me achieve this, including but not limited to: components and systems that reduce engine emissions and improve MPG, alternative fuels, and electrification of buses and all accessories. I want the per mile cost to operate the bus to go from $0.98 cents to less than $0.30 cents. ” Here are some recent advances in climate control technologies that support “energy efficiency and sustainability”. • Controls: Mechanical controls are now microprocessor based with J1939 communications capability. Advanced microprocessor technology can be used for energy management and conservation. • Motors: Permanent magnet and field wound are now ECDC brushless with variable speed control for energy conservation. • Heating Controls: On/Off solenoids are now motorized valves with PWM control providing energy conservation during the reheat mode. • Capacity Control: Mechanical EPR valves are now unloading compressors and electronic capacity control. The energy used by parasitic loads is reduced. • Unit Weight: Units weigh 200 to 300 pounds less. Weight matters. An empty bus gets better fuel mileage than a loaded bus. • Compressors: More efficient piston type and high efficiency screw compressors provide faster pull down capability. Make no mistake about it, everything on this list contributed to improvements in efficiency. But is it enough? Given the fact that the HVAC system is the single largest load on the bus, and a better understanding of what’s trending, it’s clear that current and future climate control technologies are driven by the need for greater efficiency. The trend with the greatest impact is electrification. The trend towards HVAC electrification has been around for some time but has taken on new momentum recently as users realize the value proposition through field trials and testing. Did you know that you can have an all-electric HVAC system on a conventional diesel or CNG powered bus? This technology is available from transit HVAC suppliers and can be considered as one of the latest advancements. 4

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The one-piece all-electric Athenia AMII E-800 from Thermo King is a hermetically sealed rooftop unit for hybrid bus, trolley bus and alternator-powered applications.

Here are the benefits of all-electric HVAC that will help drive down your cost of operation. • Saves fuel by eliminating the effect of variable engine RPM on bus load and cooling demand • Constant A/C unit capacity at all bus speeds including idle. Capacity is not dependent on engine speed. • Dramatically improved reliability because the units are hermetically sealed and tested at the factory. No field plumbing, evacuation and charging in the field is necessary. • Hermetically sealed, integrated electric compressors with variable speed control to eliminate belt-driven parasitic loads • A reduced number of maintenance items and components that can fail • No tubing or hoses needed in engine compartment to connect the HVAC unit and compressor. Potential leak points are eliminated. For the all-electric battery bus, which is gaining popularity, it is a given that you must have an all-electric HVAC system. While the same benefits are available, the all-electric bus is driving further improvements in climate control technology such as smaller and even more efficient HVAC systems. Here, efficiency is related to the range of the bus before the batteries have to be recharged. Naturally, the focus is on the HVAC system which happens to be the largest load on the battery. You can expect continuous improvement. I will close with this final thought: In its pursuit of improved efficiency, the industry must not forget the original intent of HVAC – passenger comfort. Our goal must be to provide the most efficient HVAC system possible without compromising passenger comfort. Steve D. Johnson, Sr. serves as product marketing manager, Bus HVAC, at Thermo King, Minneapolis, MN. Thermo King is a world leader in transport temperature control systems for buses. Thermo King also manufactures auxiliary power units, which dramatically reduce engine idling. All Thermo King products are backed by a nationwide dealer network. Visit www.thermoking.com for more information.

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Ensuring durability By Steve D. Johnson, Sr.

Modern HVAC units must be durable in many environments and road conditions, because any HVAC failure means pulling a vehicle off the road.

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n the early days of transit, it was not completely uncommon for an HVAC system to look as if it had fallen off the back of a bus after the vehicle hit a pothole. Let’s talk briefly about why that scenario is not likely to occur today by examining some important requirements in the transit industry that not only affect HVAC suppliers, but all suppliers. I can’t speak on the North American transit industry without commenting on its unique characteristics. It is part of the smallest public transportation system in the world. We produce between 5,000 and 7,000 buses a year. A single OEM in countries with multiple OEMS can produce as many as 12,000 buses a year. Our industry is federally funded and buses must run a minimum of 12 years or 50,000 miles. Many agencies are now keeping buses for 15 years. With these requirements in place, it becomes pretty clear as to what drives the demand for durability. The HVAC is now like the engine, transmission and brakes. A failure means the bus will not be in service that day. How do we ensure durability? It starts with design. We design for the conditions that the bus will see and the design must be robust enough to live in those conditions for 12 years. That sounds straightforward enough, but how do we know when we’ve got it right? We must rely on testing, validation and most of all collaboration. Testing: The testing regiment comes in two pieces. First, HVAC OEMs take a road profile from a bus in service. The bus is instrumented and the levels of shock and vibration that the HVAC unit would experience are recorded. This test is useful when something breaks to help understand why it broke so preventative measures can be taken. It is most useful for new designs. Next, the HVAC unit is subjected to the shock and vibration levels recorded on the road test. This can be done prior to the HVAC system being installed on a bus.

Validation: Of course, the best validation would be many hours in service without a failure. Unfortunately, we can’t afford to wait and see what breaks. The solution is accelerated testing, also known as endurance testing where the conditions are repeated nonstop 24/7 for a period of time to simulate thousands of hours or miles. For our industry, new bus designs must be tested at the Altoona test facility with HVAC units installed. There buses are subjected to accelerated testing before being approved for transit duty. Collaboration: As noted above, this is probably the most important piece of the equation that has enabled us to move from things breaking and falling off the bus prematurely to more robust designs. Collaboration drives more than the structural design. It drives all aspects of the design including, but not limited to, operating in extreme conditions, individual component design and overall life cycle cost. Collaboration starts with our transit partners who are the stewards that make sure the funding is used for the purposes intended. Transit agencies need to know what to put in the specifications and work with suppliers to test new technologies as well as perfecting existing technologies. It is this collaboration that makes North American transit one of the strongest public transit systems in the world. Steve D. Johnson, Sr. serves as product marketing manager, Bus HVAC, at Thermo King, Minneapolis, MN. Thermo King is a world leader in transport temperature control systems for buses. Thermo King also manufactures auxiliary power units, which dramatically reduce engine idling. All Thermo King products are backed by a nationwide dealer network. Visit www.thermoking.com for more information.

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Eco-friendliness is a priority for HVAC By Steve D. Johnson, Sr. There is little doubt that when the term “eco-friendliness” is used, practically everyone can grasp the meaning because of the emphasis on being green and protecting the environment. It is also generally understood that the HVAC system has the potential to negatively affect the environment because of the refrigerant gases inside. But before we get into the potentially harmful effects of refrigerant gases, let’s dig deeper into the broader interpretation of eco-friendliness and being green. For a product to claim that it is eco-friendly, the manufacturer of that product must have a “cradle to grave” strategy that clearly indicates that thought and effort have been applied towards creating specific rules intended to reduce the overall environmental impact. For example, every manufacturer knows what percent of their product is recyclable because it was considered during the design phase. The higher the recyclable content, the more eco-friendly the product is. The recyclable content is generally high for HVAC systems because of the common use of aluminum, brass, steel and copper. While that is a good thing, being eco-friendly goes beyond the materials in the unit. The chemicals used in the manufacturing of the product are also important. Why? Although some chemicals may be legal to use, it is the disposal of those chemicals and the potential effect on human health that drives manufacturers to use the most eco-friendly processes available. When you replace solvents and hazardous chemicals with biodegradable solutions, you can claim that your processes are eco-friendly and you are thinking green.

The manufacture of an eco-friendly HVAC product requires some special considerations. The systems designed for our comfort contain gases that can be harmful. The stage was set in 1987 with the signing of the Montreal Protocol which eventually led to legislation that phased out certain gases like R12 and R22. The issue then was ozone depletion. No ozone depleting gases are currently being used in bus air conditioning. The issue now is global warming and the stage is being set for the next transition with the EPA working on the final rule for acceptable gases. The implications for HVAC manufacturers have not changed since 1987. To be eco-friendly, the HVAC system must be designed for containment number one, and efficiency number two. Containment simply means that the design should be such that the amount of refrigerant leaking into the atmosphere is kept to the lowest level possible. HVAC manufactures have consciously reduced the number of fittings and other potential leak areas over the years. Containment also means that the user should repair any refrigerant leak immediately and observe all of the rules around recovery and recycling to further reduce the amount of refrigerant escaping to the atmosphere. As you can see, the responsibility for an eco-friendly outcome is shared. So, how does the efficiency of the HVAC system play into the eco-friendly and green scenario? Maybe more than one might suspect. Let’s start with the fact that the HVAC system is the largest single load on the bus. The power taken from the engine, or battery in the case of all-electric, to provide enough cooling for the bus can vary widely depending on the configuration of the HVAC system. An eco-friendly HVAC system is one that is designed to reduce and manage energy consumption. This measure of efficiency manifests itself with improved fuel economy for engines and longer ranges for the battery bus. While the engine itself must be efficient and comply with emission standards, any load reduction contributes to even lower emissions. Weight matters as well. As is commonly noted, an empty bus gets better MPG than a fully loaded bus. HVAC systems weigh 200 to 300 pounds less than they did 15 years ago. All HVAC manufacturers have a set of “Green Technologies” in their portfolio. Improving efficiency in the pursuit of bringing increased value to the end user is not new for HVAC manufacturers and today, the entire Transit industry is focused on energy efficiency and sustainability. To be eco-friendly, we must think and act green. It truly is a state of mind where thought leads to execution. Steve D. Johnson, Sr. serves as product marketing manager, Bus HVAC, at Thermo King, Minneapolis, MN. Thermo King is a world leader in transport temperature control systems for buses. Thermo King also manufactures auxiliary power units, which dramatically reduce engine idling. All Thermo King products are backed by a nationwide dealer network. Visit www.thermoking.com for more information.

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Preventative maintenance By Steve D. Johnson, Sr. When it comes to HVAC system performance and reliability, there is no substitute for a proactive, well planned year-round maintenance strategy that focuses on preventing – rather than fixing – problems. Performing maintenance tasks at recommended intervals helps ensure that fleet operators stay on schedule and avoid breakdowns and service disruptions. A good example of why this is more important now than ever is the dramatic drop in the number of buses transit agencies designate as spares. Who wants a $500,000 asset sitting idle just waiting to be used or undergoing a major repair that could have been handled before it became catastrophic? In some cases, everything else on the bus is working just fine when an unexpected, major failure of the HVAC system forces the asset to sit idle or be taken out of service prematurely. Ideally, if I have a 100 buses available I want 95 of them ready for service every day. Some number of buses will always be out of service for scheduled maintenance and repairs. PREVENTATIVE MAINTENANCE (PM) INTERVALS Maintenance intervals should be scheduled, focused on specific items to be checked and the results should be recorded. Operators usually perform preventive maintenance inspections and routine service on their buses based on the number of miles that have been driven. Because it is most convenient for operators to perform HVAC unit maintenance at the same intervals they use to service the bus engine and chassis, HVAC suppliers use a blended approach that considers both mileage and hours when structuring a PM schedule. For example, many transit companies change engine oil, lubricate the chassis and go through an inspection checklist at 6,000-mile intervals, adding other maintenance tasks at multiples of 6,000 miles. THE ABC’S OF PM SCHEDULING The 6,000 mile PM check can be the A inspection which comes due about every 30 days or monthly. At this inspection the technician will change or clean the air filter, do visual checks and validate proper operation of the system. The 18,000 mile check would be the B inspection which comes due about every 90 days or quarterly. The B inspection includes the A inspection plus more physical checks like adjusting the air gap on the compressor clutch. The annual or C inspection which will come due at approximately 48,000 miles is a comprehensive check of all systems and components. The C inspection includes both A and B inspections and is the ideal time to replace worn parts before they fail.

Allow the system to breathe by washing coils annually and changing the air filter monthly.

Operators often modify the ABC approach to fit their fleet profile and local operating conditions. In areas where the air conditioning season is short, agencies might use the seasonal approach. Spring is probably the best time for the Annual Inspection. Keep in mind that there are also some very specific checks that should be done each autumn in preparation for the heating season. PREVENTATIVE MAINTENANCE AND NEW TECHNOLOGY Ask any tenured technician in the automotive industry and they will tell you that preventative maintenance practices have changed dramatically. This holds true for the HVAC system as well. Complex electronic systems driven and monitored by highly advanced microprocessor controllers with diagnostic capabilities have significantly reduced the time it takes to diagnose and repair a failure. Advancements in clutch and motor technology have come with longer maintenance intervals. Additionally, the PM check for all-electric HVAC systems can be done in less than half the time needed for a conventional system because there is much less to check. PM TIP: CHANGE AIR FILTERS MONTHLY, WASH COILS ANNUALLY Clean filters and coils keep the system breathing easily. Changing or cleaning the air filter is one of the easiest PM activities you can do, yet it remains as one of the most neglected. A severely restricted air filter or coil not only affects system performance, it can contribute to unexpected system failures. Prolonged operation affects fuel economy and will shorten the life of major components like the compressor and fan motors. Steve D. Johnson, Sr. serves as product marketing manager, Bus HVAC, at Thermo King, Minneapolis, MN. Thermo King is a world leader in transport temperature control systems for buses. Thermo King also manufactures auxiliary power units, which dramatically reduce engine idling. All Thermo King products are backed by a nationwide dealer network. Visit www.thermoking.com for more information.

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