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mileyjean's avatar
mileyjean
Explorer
Jun 17, 2015

Leaking air conditioner

We purchased a new travel trailer and have taken it out a few times and when we run our air conditioner it is fine and does not leak until it starts to rain. It does not leak when air is not on so it is not a leak and it does not leak if the air is on and it is not raining. Help just a little confused and I assume it has something to do with the drain hose but just not sure exactly how it all works and why rain would play a role.

7 Replies

  • Gotta love these forums. Exactly the same thing just happened to my one year old unit. Mine is a Coleman Mach. About a quarter cup of water just poured out of the corner nearest the thermostat. This was following a two inch downpour and the first time that it has happened. I wonder if icing was involved since it is extremely warm and humid.
  • When you say leak, you mean it is dripping out of the bottom of the unit?

    You could have condensation building up because the return air and discharge are mixing. If humidity is very high this will be a problem. Remove the inside cover and you will see a liner between the return and discharge vents. Look at it and see if there are any holes in it. You can fix it easily with duct tape.

    You could have a loose roof seal that gets overwhelmed when it rains combined with all the discharge moisture.

    I would pull the inside cover, check the liner, and also tighten the four bolts a turn. See if that works.
  • If it is an easy fix I would rather do it myself since the dealer is an hour away and don't really want to take it in and not have it this time of year. I will wait until fall if it is something that I can't easily fix since I can still use it as long as I don't run my air when it is raining. If it is the gaskets why does it not leak when I am not running the air or when it's in storage and it rains? Wouldn't it still leak then?
  • My guess is that it's the condensate drain has a wasp or bee in it.
    This could happen if it's raining because A/C units cool by removing moisture from the air. If it's raining, you have max moisture. Pull the cover of your unit (4 screws) and look around the bottom pan and see if you can find the drain. Wasps love RV A/C units. I've been nailed twice by wasps in 20 yrs. both times it was on a RV A/C unit.
  • Likely the gasket between the roof and AC needs tightening.

    Remove the inner grill and there should be 4 bolts (one in each corner) that you can tighten up BUT DON'T OVER DO IT!

    If it is new take it in for warranty?

    Check the manual that you should have received with the camper for proper tightening.

    Check this for answers.

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