Forum Discussion

hoodidean's avatar
hoodidean
Explorer
Aug 23, 2016

AC going off and on and off and on........

We have a bunkhouse 5er with 2 a/c's. The main unit will run until it reaches what the thermostat says and kicks off, then in 30 seconds or so, it kicks on and then 30 seconds later off and does this repeatedly until we either bump it up/down a degree or two, then it runs to that temp and we start all over. It will stop if the outside temp goes below the setting. Sometimes the compressor comes on and sometimes it's just the fan. Doesn't matter if the bedroom unit is on or not. The thermostat has been replaced twice and the rooftop unit once.
As you can imagine, it's very irritating. Anybody have any words of wisdom?
  • Second_Chance's avatar
    Second_Chance
    Explorer II
    Aug 23, 2016
    Have you noticed the fan changing speeds during any of these episodes? Most RV A/C units have two-speed fans. The A/C will run with the fan on high until the inside temp reaches a certain point. The unit will then cycle the fan off and back on at the lower speed. Upon "discovering" that it can't hold the set temp with the fan at low speed, it cycles the fan off and back on at the higher speed again. Sometimes units will even skip the low speed part! If this is what's happening to you, some people have gotten around it by setting the fan on a particular speed (full-time rather than auto) and then setting the thermostat back to "cool" at the desired temp. The fan will then run all the time with only the compressor cycling on and off.

    Rob
  • sdianel_-acct_c's avatar
    sdianel_-acct_c
    Explorer
    Aug 23, 2016
    Recently we had the same problem. A service tech said that in high temp and high humidity situations that the fans must remain on high (both of them). That puts more air across the condenser and keeps the units from freezing. Since we've been doing that no problems. Turn both units off completely or on fan high (not cool setting) for about half an hour, then turn back on cool setting with fans "high"... see if that works. What brand AC and what brand and model of thermostat??

About Full Time RVers

1,587 PostsLatest Activity: Dec 28, 2024