Forum Discussion

Rodeo13's avatar
Rodeo13
Explorer
Sep 03, 2013

A/C filter, freeze up

I have a Duo-Therm a/c and it just started freezing up. I've tried to find the filter since buying my t. t. 3 mos. ago. Nothing inside or out. It has cooled great until going home this past weekend. I turned it up to 76 before leaving so it wouldn't run all wknd. I got back tonight and its frozen up. What can this be and where should the filter be?

9 Replies

  • 77charger's avatar
    77charger
    Explorer
    Sep 03, 2013
    Only time i ever had an a/c freeze up is when i ran the fan on low.Now i run them on high never a freeze up
  • Rodeo13's avatar
    Rodeo13
    Explorer
    Sep 03, 2013
    Thanks everyone for the help.I didn't have a filter in mine,thats why I couldn't find it.I have one now. I cleaned the coils and put a new filter in. I bought the trailer used,have a book on everything except the a/c.
  • time2roll's avatar
    time2roll
    Nomad
    Sep 03, 2013
    dougrainer wrote:
    IF you have a wall tstat (you must since you said 76 degrees), your unit has a Freeze sensor that keeps the unit from freezing. THAT is what you need to check. Make sure it is installed in the evaporator. IF the freeze sensor is installed and functioning, NOTHING will cause a freeze up. Doug
    +1 on this.
    Remove the interior trim to get access.
  • Old-Biscuit's avatar
    Old-Biscuit
    Explorer III
    Sep 03, 2013
    Roof mount A/C unit......filter should be under ceiling grill.

    You may have to remove the whole grill to access it
  • beemerphile1's avatar
    beemerphile1
    Explorer
    Sep 03, 2013
    Most common reason for freeze up is inadequate air flow. Find and clean the filter, run fan on high. Make sure all vents are open.
  • dougrainer's avatar
    dougrainer
    Nomad
    Sep 03, 2013
    IF you have a wall tstat (you must since you said 76 degrees), your unit has a Freeze sensor that keeps the unit from freezing. THAT is what you need to check. Make sure it is installed in the evaporator. IF the freeze sensor is installed and functioning, NOTHING will cause a freeze up. Doug
  • fpresto's avatar
    fpresto
    Explorer
    Sep 03, 2013
    Obviously the filter is the first thing however if the humidity was high like it was here and you left the fan on low that could also cause it to ice up. In high humidity conditions most manufacturers recommend running the fan on high.
  • LarryJM's avatar
    LarryJM
    Explorer II
    Sep 03, 2013
    Rodeo13 wrote:
    I have a Duo-Therm a/c and it just started freezing up. I've tried to find the filter since buying my t. t. 3 mos. ago. Nothing inside or out. It has cooled great until going home this past weekend. I turned it up to 76 before leaving so it wouldn't run all wknd. I got back tonight and its frozen up. What can this be and where should the filter be?


    I a ducted system, it's under the return air grill which is shown in your operating instructions that came with the trailer.


    Larry

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