Every day, people across the world sprint to their nearby bus stop in a tardiness-induced panic, only to watch as the bus they should already be seated on passes by. Others sit stewing in the hot sun, waiting for the next bus to arrive. Unfortunately, transit vehicles cannot control the varied schedules of their individual riders. The next best thing, however, is to control the schedules of their stops and the conditions onboard the bus. To a waiting transit rider, there is comfort in knowing that the next bus will be air-conditioned.
Manufacturers of air conditioning and climate control systems are aware of the comforts that a cooled vehicle can provide to its riders. It is crucial for these companies to provide dependable, lasting and efficient systems to transit agencies. Furthermore, it’s just as important for the agency to provide the same level of service in how it employs climate-control systems.
“Obviously, in hotter climates, air conditioning becomes front and center on the list of concerns for transit agencies,” says Curtis Kiser, transit sales manager for Carrier Transport Air Conditioning. “Transit riders do not like to ride buses that are too hot in the summer or too cold in the winter. So, the climate-control system is critical to customer satisfaction, and thus income for a transit agency.”
Climate control, rider relief
For bus operators, whether in service for private or public transportation, or utilizing school, shuttle, transit or any other types of buses, air conditioning and climate control systems are as important to them as they are for those riding their vehicles.
Customer comfort and satisfaction is directly linked to the air conditioning and climate-control systems running on a particular bus. It can mean the difference between return passengers who know the name of their regular bus driver and passengers who will never board a bus again.
“In the U.S., an air conditioning system is considered a major bus component like an engine or transmission,” says Steve Johnson of ThermoKing Corp. “If it goes down, the bus doesn’t operate.”
According to several representatives of mobile air conditioning manufacturers, climate control is also a very important tool in curbing unruly or violent behavior among bus riders. Generally speaking, across all forms of bus transportation, people who are less hot are less frustrated, and less likely to cause a problem.
The trend of outfitting transit buses with air conditioning systems is nothing new and can be somewhat attributed to the Americans with Disabilities Act (ADA), which mandates provisions about HVAC (heating ventilation and air conditioning) systems. The ADA recognizes that air conditioning is also a necessity for the health of elderly and disabled passengers.
Failure-free operation of air conditioning and climate-control systems is imperative to the bottom line of transit agencies. Several components, such as the compressor, electromagnetic clutch, expansion valve and a host of other technical gadgets, keep an air-conditioning system up and running. However, air conditioning units are known to need a disproportionate amount of attention compared to other bus components. The issue of whether a certain component or system will fail is not about if, but, rather, when.
“The key for transit agencies is to give their air conditioning the same care they would give an engine,” says Cheyne Rauber, general manager of Rifled Air Conditioning. “If they don’t, it just won’t last as long as they want it to.”
The most common problem, according to Casey Cummings, vice president of ACC Climate Control, is air conditioning leaks. While a leak may sound relatively benign, its effects are malignant. A leak is the first thing that causes a cascade effect of other problems, particularly losing refrigerant and oil.
“People don’t diagnose these leaks correctly, from transit buses all the way to shuttle buses,” says Cummings. “The biggest thing with buses is the lack of maintenance or the lack of visual inspections. Most guys don’t do what they’re supposed to do and that causes early failures.”
With it a given that air conditioning and climate-control systems will at some point fail or break down, what options do transit agencies have to get their buses out of the shop and back on the streets as quickly as possible? Time is of the essence. Many transit agencies do not have a large fleet of spare buses prepared to run on a day’s notice.
There is no magic bullet to ultimately solve the problem. Most transit professionals stress the importance of preventive maintenance. Like the often-used sports cliché, regular servicing ensures that “the best offense is a good defense.”
“Ambivalence about routine maintenance,” says Carrier’s Kiser, responding to what is most problematic about air conditioning systems and the reasons they breakdown. “Just because the air conditioning works fine does not mean the transit operators should forego routine maintenance.” Many tend to believe that if it isn’t broken, don’t fix it. But air conditioning systems require periodic maintenance just like the engine, transmission and other components.
Climate control trends
New trends in climate control and air conditioning systems represent improvements over the systems of previous years, but as far as seeking newer systems to improve fuel efficiency or reduce breakdowns or failures, no groundbreaking industry developments are in sight. While newer systems will last longer, improving
reliability and durability in a sense just serves to delay the inevitable breakdown or failure at some future point.
“Refrigerant has been an issue ever since the EPA took over governing the emissions of vehicles,” says Kiser. “It is an ongoing process to search for the cleanest and safest refrigerant that will operate efficiently in current air conditioning technology.”
Newer EPA rules will mean changes. Non-ozone-depleting HFC-134a seems to be the refrigerant of choice over the last few years, as HCFC-22 will be phased out beginning in 2010. Also, when EPA standards for diesel engines change in 2007, a range of issues will likely fall at the feet of bus OEMs due to larger radiator requirements.
“Many are looking at ‘attic’ radiators, which will mount over the top of the engine in transit buses,” says Kiser. “This space has traditionally been reserved for rear-mount air conditioning systems. We may well see a trend to roof-mounted air conditioning systems as a result, which will be a rather large change for many transit agencies.”