What does a Freightliner air conditioner compressor sound like?
What does a Freightliner air conditioner compressor sound like? Freightliners use a simple dial on the HVAC control unit to control the setting of the AC system. On a freightliner, the sound of the compressor starting is unmistakable. You should hear a low "hum" followed immediately by the cooling fan turning on. How to troubleshoot a / C problems in Freightliner Trucks? A specially trained mechanic should fix any problems with the AC system, but you can troubleshoot to verify that there is a problem. Turn the engine on and allow the truck to warm up to its normal operating...