Looking for A/C condensation solution

[barclay7568]

2004 Allure, 36', 2 Duo-Therm A/C units, one front and one rear. The rear unit drips water onto the bed after @ 4 hours running on high.

A couple weeks ago, we found ourselves dry camping in 100 degree weather and were running both a/c units. The rear started dripping water (did this a couple years ago and I never located the cause) so I removed the plastic housing from the ceiling. The housing was full of water and the metal frame on the ceiling had condensation droplets on it's entire surface on the air discharge side. The air intake side of the metal framing was dry. I'm guessing that the interior air has sufficient moisture (outside humidity was 17%), and the a/c was producing COLD air, that the metal framing was so cold it created the condensation. The droplets off the metal fills the housing with 3/8" to 1/2" water over a period of time, then when the housing is full, it overflows out the air discharge grate onto the bed. The air intake side of the unit has what looks like two water lines connected with a "T" which I assume vacates the condensation from the coils on the upper part of the a/c unit so I don't think that's involved in this problem.

I was thinking of using duct tape (or other thick tape) to cover the metal framing to prevent the droplets from forming on the metal.

Has anyone else experienced this when in extremely hot weather?

Any help would be appreciated.

joe

[smlranger]

Those lines drain condensation down to the ground under the coach. If they are stopped up, you can have that issue. Take the fitting apart, and blow air into the hose. My drains are at the left rear, amidships and left front. When I blew air in my rear AC drain hose, a bunch of goo came out on the ground along with a lot of water. No more issues after that.

Some of the roof AC's (may all that CC used) use a little sump pump that pumps the condensate out that hose. You may need to get on the roof, remove the AC shroud and check those if you have them.

[clydeman]

Barclay, this may sound strange, but sometimes when the return air filters get dirty they restrict the air flow and this will cause condensation to build up and drip inside your coach, it happen to me, so I clean mine every month or two under heavy usage, I also have the cond. pump on mine too which I blow back now and then just to keep them clean.. Good luck .

[barclay7568]

Yup. I cleaned the filters and took the "T" apart and blew air through both ends--nothing ended up on the ground and the air did not appear to meet and resistance. We've used the coach every week since and have not had the need for the A/C so don't know if the air did any good or not. I'm going to take the shroud off in the next week or so while I have it parked in the barn and have a look under the hood. The thought also occurred to me that when parked, and believed to be level, if the back of the coach was actually lower than level, could the condensation buildup in the pan leak into the rear portion of the air outlet inside the coach because it gets to that point before arriving at the drip lines in the forward part of the pan? Just a thought. Maybe I can see more when I take it apart.

[Smitty77]

While up on the roof, take your compressor and blow from the inside of the coil out, knocking off any loose dirt or other debris. Get a can of coil cleaner, and spray it onto the outside of the coil, comes out of the can and foams well. Easier to get the one that is spray and leave on, as it evaporates. (We've been in some hot temps the last month or so, and even though the units were serviced about 8 months ago, I went up and did another one get maximum cooling capability.)

And finally, from inside of the coach, double check that the four bolts holding the AC unit to the roof, are snugged up. They sometimes loosen up with vibration. I check mine each during my annual Thanksgiving maintenance cycle on the coach. Don't tighten too tight, as that can damage the gasket between the AC unit and the roof. While poking around inside, make sure none of the drain hoses were damaged, or have loose hose clamps. While up on the roof, also check the pan is not cracked. If it is, that and a the four bolts not snugged down, could cause a problem. And who knows, maybe a previous owner had the AC unit worked on, and the gasket to the roof was damaged?

Those are my thoughts, but mostly hope - that you have no need for maximum AC as you travel!

Best,
Smitty

[tim myers]

Haven't heard anyone suggest cleaning out the condensate pan. I had similar issues with my rig a couple weeks ago. Turned out one of the holes in the pan was completely blocked and one was partially blocked. South Carolina humidity overwhelmed the unit and it started to rain inside. I had to disassemble the AC unit and shift the evaporator coil out of the way in order to get a shop vac nozzle in the pan and suck out the foreign material.

My roof AC unit drains onto the roof of the MH.

As a preventative I am thinking of putting some condensate pills in the drain pan. They dissolve slowly releasing some chlorine in to the pan that helps eliminate the slime that can build in in condensate pans. A system with an actual drain hose would benefit even more I think.

[barclay7568]

I have a free day tomorrow so will take it apart and look at it.

Smitty77, where do you get the coil cleaner-auto parts store??

[barclay7568]

Disregard my last. I see HD and Lowe's both carry it.