ACtion Magazine - July 2012 - (Page 28)

by Stephen Petit, SiefkesPetit Communications N early every town has one: a fire truck or emergency vehicle that needs A/C work. “These vehicles are generally well cared for but basic A/C service often is not part of the preventive maintenance routine,” says Gary Hansen, vice president of Red Dot Corp. in Seattle, which supplies factory-installed and aftermarket HVAC units for fire apparatus and other heavy-duty vehicles. evaporator, and so on—should be familiar to any qualified A/C technician. They simply require more consistent maintenance, which is why fire apparatus and emergency vehicles can be an opportunity for A/C shops to pick up additional preventive maintenance work. Here are five things to consider if you want to maintain fire and emergency response apparatus. Service Intervals A faulty A/C unit is a concern beyond the comfort of firefighters responding to a call, and the vehicle isn’t just transportation. The cab is also a safe place for firefighters and emergency workers to rest and recover on-scene. These are large spaces, often with multiple A/C units. “You have an under-dash unit for the front compartment where the driver and an officer sit, and one or more overhead units for spot-cooling in the crew area, where in some vehicles, you might have eight people in full bunker gear,” Hansen explains. “So these are big, beefy systems that have to work long and hard to deal with a lot of BTUs, dust, and humidity. A dual-evaporator system can have more than 9 pounds of refrigerant and 65 to 80 feet of A/C line. The suction line may run 20 feet.” Still the basic components—compressor, condenser, 28 ACTION • July/August 2012 A fire truck in a small community might have a service life of 20 years and see only a few calls a month, while a big-city fire department may dispatch a truck any time it sends out an ambulance. Duty cycles vary wildly, and with so many different maintenance schedules to keep track of, the A/C gets lost in the haze. Still, every vehicle needs to have its engine oil changed—make A/C inspections part of that routine. “Whether it’s done by the mile, by the month, or by the operating hour, use oil-change intervals as your guide to scheduling A/C inspections,” Hansen says. “Any time that truck goes into the shop, use that planned downtime to perform a basic visual check of the compressor and belt-drive system, condensers, receiver-driers, expansion valve, evaporators, and other components.”

Table of Contents for the Digital Edition of ACtion Magazine - July 2012

ACtion Magazine - July 2012
Contents
Outlook
Expansion Valve
Technically RELAY-ted
Under the Southern Cross
Leonard’s Law
Cooling Corner
Virtual View
News & Updates
KME: Where Custom Is the Norm
Five-Alarm Maintenance
ACtion Magazine Staff Win IAMC Awards
Association News
Quick Check
New Products & Services
Last Watch

ACtion Magazine - July 2012