Forum Discussion

jstaffon's avatar
jstaffon
Explorer
Feb 04, 2019

Water leak at air conditioning vent

I have a 2016 Rockwood 5th wheel with two Coleman Mach air conditioning units (the one in the bedroom being a heat pump). The rig also has two MaxAir exhaust fan units.

Inside on the ceiling of the main part of the camper, mid way between the two air conditioning units is a cold air vent that sometimes drips water during rain storms. The vent also is near one of my MaxAir fan units. The ceiling doesn't seem to be damaged and the roof seems to be still sealed well with no cracks in the sealant. The weather is such I haven't had to run the air conditioner...it seems to be associated with the rain we've gotten. It's almost like water gets into the air conditioning unit somehow and runs down the exhaust hose to the vent in the ceiling. Does anyone have any ideas? Thanks in advance!
  • jstaffon's avatar
    jstaffon
    Explorer
    Feb 05, 2019
    Super_Dave wrote:
    jstaffon wrote:
    Sounds like a complicated installation. Is there a way to inspect it to make sure there's a leak? What's the fix? Is it a DIY project or does it have to be removed and reinstalled the right way?

    Don't sweat that problem yet. Just look at the flanges and see if they are 1/4" - 1/2" above the roof deck and not sitting in sealant.


    I've watched a couple of Youtube videos about installing the unit. They show a plastic roof flange that sits on the roof and has some tape sealant under it with some screws holding it to the roof and then sealant around the edge of the flange and on the screw heads to seal it. The fan unit then sits on the plastic flange. Is that the "flanges" you're talking about? Is that something I can see from inside the camper or do I need to be on the roof and remove the fan unit? Sorry....I'm confused. I'm not sure exactly where the leak would be either.
  • donn0128's avatar
    donn0128
    Explorer II
    Feb 04, 2019
    Like has already been explained. Take the inside plastic grill off. You will find 4 small bolts. Carefully and evenly snug them down. Torque? Maybe 4inlb. It takes very little torque to overtighten them. Use a 1/4 inch ratchet and using your weak hand twist it a bit if the screws move then you might have found the issue.
  • Super_Dave's avatar
    Super_Dave
    Explorer
    Feb 04, 2019
    jstaffon wrote:
    Sounds like a complicated installation. Is there a way to inspect it to make sure there's a leak? What's the fix? Is it a DIY project or does it have to be removed and reinstalled the right way?

    Don't sweat that problem yet. Just look at the flanges and see if they are 1/4" - 1/2" above the roof deck and not sitting in sealant.
  • jstaffon's avatar
    jstaffon
    Explorer
    Feb 04, 2019
    Sounds like a complicated installation. Is there a way to inspect it to make sure there's a leak? What's the fix? Is it a DIY project or does it have to be removed and reinstalled the right way?
  • Ralph_Cramden's avatar
    Ralph_Cramden
    Explorer II
    Feb 04, 2019
    I bet you have the factory installed Maxxair covers on the Vent?

    If so I also bet Rockwood installed them while the lap sealant was wet on the line and has them mashed into, and stuck into, the sealant. The way the Maxxair covers are installed is with pins that clip into plastic tabs, that are molded into the flange on the Maxxair vent/fan. The tabs are open to the underside of the flange. If Rockwood missed with the sealant and tape under that flange, not getting it directly below the tab, those pins will leak every time. It's a known issue with those factory Maxxair fans and covers, especially when Rockwood is involved.
  • jstaffon's avatar
    jstaffon
    Explorer
    Feb 04, 2019
    Great suggestion!

    What kind of bolts are they and what are they screwing in to? About how much torque is the right amount?
  • Super_Dave's avatar
    Super_Dave
    Explorer
    Feb 04, 2019
    I got lucky and was on my roof and noticed that the AC unit had shifted a bit. I took the inside diffuser off and saw that the bolts were loose. So, I concur with everyone else on this one.
  • donn0128's avatar
    donn0128
    Explorer II
    Feb 04, 2019
    Loose AC housing. The AC units are bolted down using 4 screws. Seal is provided hy a foam gasket. As the gasket ages it can shrink, the bolts can work loose. Either can allow water past the seal. Very carefully snug the bolts down evenly a bit and see it thst stops your issue. If not, buy new gaskets.
  • freewayrandy's avatar
    freewayrandy
    Explorer
    Feb 04, 2019
    Pull the cover off the ceiling a/c unit and check the 4 bolts that hold the unit. They have a tendancy to vibrate loose.

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