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KotzurJ's avatar
KotzurJ
Explorer
Oct 08, 2023

Thermostat not getting 12v

Hey guys, first post just recently started full timing in a 2004 KZ inc. New Vision 34’ 5th wheel. Everything worked great until last week, the a/c started short cycling and the LP leak detector started screaming and showing a fault. I replaced the thermostat which changed nothing big surprise. I can’t seem to figure this out. I test for voltage at the thermostat and I’m getting 1.67v so I’m figuring loose connection somewhere. I bypassed the leak detector thinking that was causing an issue but it didn’t solve anything. Breakers are alll fine, fuses are good, we are connected to shore power. No other power issues only the thermostat. I’m searched but couldn’t find anything already posted. If anyone has any ideas please let me know. I have a Coleman Mach cool/heat slider thermostat, a airxcel rooftop ac, and I don’t know what brand of furnace, it’s right beneath the stove if that helps. Coming into winter just trying to get this furnace burning.
  • KotzurJ's avatar
    KotzurJ
    Explorer
    Oct 08, 2023
    The Furnace stickers just say Suburban Manufacturing company Dayton, TN 37321. Direct vent system appliance.
  • KotzurJ's avatar
    KotzurJ
    Explorer
    Oct 08, 2023


    Theres the Thermostat and the wires, I copied the old thermostats wiring . I will remove the furnace cover and post a picture whenever it is done. Thanks! I also have a battery hooked up currently and it is not making a difference.
  • dougrainer's avatar
    dougrainer
    Nomad
    Oct 08, 2023
    1. The wall tstat will NOT cause short cycling
    2. You HAD to have miswired the new Tstat
    3. Some RV makers use the 2- FURNACE 12 volt wires that go to the Tstat to POWER the tstat.
    4. Now for some fun with you. I don't know what engine I have in my car but it is located beneath the hood, Hope that helps:B
    5. Really need brand and model of furnace. Because some models have a 12 volt circuit breaker that will trip if you shorted those wires when replacing the wall tstat. Can you reinstall the original wall tstat, if you remember or wrote down the wire color codes? Doug
  • dougrainer's avatar
    dougrainer
    Nomad
    Oct 08, 2023
    corvettekent wrote:
    My Thermostat uses AA batteries. Have you checked to see if yours does also?


    RVP Tstats do not use batteries.
  • KotzurJ's avatar
    KotzurJ
    Explorer
    Oct 08, 2023
    The camper didn’t have any batteries whenever I got it, and I haven’t put any in. The ac and heat were working great for the past couple months. I tried putting a battery from my truck and hooking it up but it didn’t change anything
  • way2roll's avatar
    way2roll
    Navigator II
    Oct 08, 2023
    Are your batteries charged? Just because you are on shore power does not mean your batts are good and charging. All your 12v items run on batteries, not shore power - despite being plugged in.

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