2014 Fuzion 390 chrome main ac not working

[Sam8923]

While on generator or plugged in main ac thermostat dose not have any power. Pulled thermostat of wall checked with voltmeter no power. Checked for power at breaker and I have 120v. Applied 12v to red and white wire at back of thermostat and everything works fine. Dose anyone know where the red and black wire originate from. I just got the trailer back after it spent 45 days at dealer for warranty. Don't want to take it back.

[matandjen]

Originally Posted by Sam8923

While on generator or plugged in main ac thermostat dose not have any power. Pulled thermostat of wall checked with voltmeter no power. Checked for power at breaker and I have 120v. Applied 12v to red and white wire at back of thermostat and everything works fine. Dose anyone know where the red and black wire originate from. I just got the trailer back after it spent 45 days at dealer for warranty. Don't want to take it back.

Did it work at some point? It sounds like you may have a blown fuse.

[JRTJH]

The thermostat connections are located in the overhead airconditioner. If you remove the inside cover, you'll see the black/red/yellow connections. Chances are one of them has worked loose or had been pulled loose.

BE CAREFUL and unplug the RV from shore power before sticking your hands up there because there is also 120VAC on some connections and it's possible to grab the wrong wire !!!!!!!

[Sam8923]

Thanks for the replies. I did check all fuses at electrical panel and reseated all plugs in the ac, but was kind of in a hurry. Tomorrow morning when I get off work I will have more time and will let you know. Just not sure if there is a common buss bar in the front by battery or in the pass through storage area.

[Anson9110]

Hi, I have worked on many rooftop industrial AC units and the first thing I check is the relay where the power is stepped down from 120VAC. I'm not sure exactly what it would look like on yours but it's all fractional. Every year I come at least one unit that I have to replace the contactors. It will fairly obvious if they are burnt or worn. To check for anything else you would have to let me know if the unit was running properly before.

[Sam8923]

Yes everything worked fine before. If I take 12v and apply it directly to the thermostat it works fine. The wires that supply the 12v to thermostat read 0v. That is what I am trying to chase down is where those wires come from. Talked to a tech at dealer he told me they come from fuse panel and if I can't find the problem to run wire from a 12v source to thermostat for a temp fix. i was going to use the camper this weekend and canceled the trip due to this problem. 80+ degrees in south florida not fun with 2 kids. Thanks again.