Water dripping from heat pump

[Loren]

Our trailer has a Duo-Therm Penguin air conditioner/heat pump. There is a drain line that runs from it, through the trailer wall, to the bottom of the trailer.

When we use the unit as a heat pump, water will drip from the inside of the unit onto the carpet.

This occurs only after an extended period of use, and seems to be related to high humidity inside the coach (as I would expect). The Airstream Factory Service Center is unable to duplicate the problem, probably because they don’t live in the trailer (creating the humidity) while running the heat pump. Since they can’t duplicate it, they can’t fix it.

The service center did blow out the drain line that runs from the heat pump/air conditioner to the bottom of the trailer, and that seemed to help. Since then, however, the problem has returned.

We have found that water will collect in the unit somewhere and when we move the trailer after using the heat pump that water will slosh around and spill into the coach onto the carpet.

The previous owner told me that he got up on the roof and “re-sealed” all the places he thought should be sealed. Could it be that he has sealed up a drain? If so, what drain?

Has anyone else had this problem? Have you found a solution?

I would appreciate any help at all.

Thanks,
Loren

[TomW]

Originally Posted by Loren

...We have found that water will collect in the unit somewhere and when we move the trailer after using the heat pump that water will slosh around and spill into the coach onto the carpet...

Off hand, it sounds like an issue of level. Your drip pan, which is collecting the condensate, probably has only one hole in it for the drain line. If the pan is not level with respect to gravity, the pan will only drain when the water reaches the level of the hole. So most of the time you would have some volume of water waiting to slosh out.

As a test for the scenario, locate what corner of the A/C the drain line attaches to and do whatever it takes (jacking one side of the Airstream or running the tongue jack up or down) and see if can get more condensate to drain.

Unfortunately, your drain pan is most likely integrated into the A/C unit itself, so it will not be possible to independantly level it - the entire unit will need to be shimmed.

Or the problem may be what the next poster says.

Tom

[Pahaska]

The drip pan should not be a factor and humidity inside the trailer should not be a factor. Outside humidity probably will be a factor. When the AC is in heat pump mode, the functions of the inside and outside plumbing are switched so that any water that is being produced is being produced on the roof. The inside coil is hot and will not be shedding moisture. There was a photo posted on this forum (by jcanavera, I think) some time ago showing a heat pump that had totally iced up outside on the roof.

When in heat pump mode the unit defrosts periodically; that will dump a lot of water all at once.

I would pull the shroud off and look for any way that water might seep from the outside down into the trailer, possibly where the tubing enters.

[jcanavera]

John, you are right on. The condensation is occuring outside in the shroud. Not in the normal area where condensation occurs when you are in cooling mode. Pull the shroud and if need be bring us a hose to add a little water. You should be able to see what's going on.

Jack

[Loren]

Gents,

Thanks for the helpful comments. I know that the heat pump defrosts the outside coils (or fins) periodically when it's in heating mode. That's why I can't understand why the water is getting inside. It doesn't get wet inside when it rains.

It makes perfect sense that the drain line is the problem, but if it's that simple, why couldn't the factory technicians at the Airstream factory find the problem? (Actually, my experience with Airstream's factory service leads me to believe that they are not at all what I would expect from factory service. I've been very disappointed -- but that's a different issue.)

I will probably be doing some roof/ceiling work soon, as I hope to install a new Fantastic Fan in the living room. While I'm up there, I'll take the cover off the heat pump and do more research. The hose suggestion is great; I'll certainly try that.

I am discovering, after a few unsatisfactory episodes with Airstream's factory service, that if I can fix a problem myself I am better off. When I do it, I may make a few mistakes along the way, and it will certainly take me three times longer than the technicians, but when I finish the job will be done right. The time to do the job isn't that big a difference if you consider that it's three hours each way to Jackson Center, plus waiting time.

Apparently, no one ever told Airstream about the hose trick. I'll see if it works for me.

Thanks again for the help.

Loren

[lbdesign]

These discussions have me concerned about relying on the heat pump function. Loren, did you find a solution to your problem? Thanks!