Yet another equipment failure in the trailer. We have been fortunate and have only used the air conditioner a few times in the last 5 months. Now that we are in the heat and humidity with temps in the 90's with high humidity we could use the AC. Perfect timing for the air conditioner to go on the fritz.
Symptom: When you turn the thermostat to the fan position the fan turns on but when you turn to the cool position everything shuts off.
Diagnostics:
1. RV heat/cool systems work off 12v for the controls. I verified 12v is present at the thermostat and the internal fuse is not blown.
2. Measured the voltage inside the thermostat at the compressor control wire and found 0v when it should be engaging the compressor.
3. Disconnected the compressor control wire from the back of the thermostat in case a short was pulling the voltage down. Still 0v when it should be 12v.
4. Jumpered the compressor control wire and verified that the compressor relay engages and 110v is present at the compressor side of the relay.
5. Thermostat troubleshooting flow chart indicates a bad thermostat.
6. Replaced thermostat.
7. Compressor now turns on. Verified through the power monitor in my power conditioner and verified the voltage on the control side of the compressor relay.
8. Air conditioner doesn't cool ! Let run for extended period of time and no temperature difference between the intact air and the output air was measured via laser temp gauge.
9. Climbed on the roof and removed the cover so I could verify the voltages and capacitor.
10. Immediately noticed a coolant leak on the compressor. Game over.
I don't believe in coincidences but I can't explain a connection between the thermostat failing and the compressor leak. But.......
The air is under warranty so I contacted a local mobile service. These air conditioners aren't designed to be repaired. The company just replaces the unit. The problem is it takes a couple of weeks to submit the paperwork and receive a new unit. We are only here for 5 more days so this isn't going to work. We could replace out of pocket but we are talking around $800-$1000. Hard to justify when we only have 2 weeks left in our travels. Looks like we will have to suffer through the next couple of weeks and get it replaced when we get back to Florida.
All of the problems we have had are with the standard components that are the same across most RV's, regardless of RV brand. Dometic fridge, Suburban furnace, Atwood water heater, Coleman-Mach AC. The majority of all RV manufacturers use these same utility components. Fortunately we really haven't had any issues with the travel trailer itself.
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