A/C Pours Water Inside When Switched Off

[smgburris]

Hello -- I'm new here. Bought a 2001 *70th Anniversary Edition* 25' Safari about 6 weeks ago and we've been re-doing it since. She's got solid bones, and the cabinetry, ceiling, and subfloor are in great shape. Mainly, it was just the dirtiest thing I've ever seen, so tons of cleaning, removal of original sofa, carpet/pad and drapes, cleaning mouse fur, etc. We've also made new plywood plank flooring that we're ready to install, BUT --- after working along for several weeks, running the a/c during the hot days, we experienced something very weird: a few seconds after we turned the a/c off, water started pouring out of the a/c unit, and I mean a LOT of water. It finally slowed to a drip, but left us totally bumfuzzled. It happened a couple of times, but not every time, and not while it was running, but only after it was turned off. My Love took the shroud off of the rooftop unit, and thoroughly cleaned the coils and the pan. The actual drain is located underneath the pan, and there seems no way to get to it. Water does run/drip out of the drain tube when the a/c is running, but the problem persists. We would so appreciate it if anyone has insight and/or advice about this problem. We can't lay our floor until we get this issue resolved, and the rest of the refurb hinges on getting the floor in, so we're at a standstill. Thanks in advance for your help!

[cwf]

Howdy! Could be a slow flowing condensate line for starters.

Are you getting condensate coming out of the street side black Plastic tube?

[dznf0g]

Possibilities :

1) running fan on high doesn't allow for water to leave the tray as easily as on low due to a lot of turbulence. Not an issue if 2 and 3 are ok

2) drain line is plugged. Run a long piece of weed whacker line up all the way into other tray. Or suck it out with wet dry vac...or both.

3) tray nipple and/or tray itself is cracked. Very common. I repaired mine with JB Weld.

[dznf0g]

The tray is accessed from the inside, with the white air plenum removed.

[drboyd]

Here's what is probably happening.

The fan draws a bit of vacuum (it doesn't take much) on the condensate drain. It's enough to let it drip a little, but it still builds up in the drain pan and on the evaporator (cold) coil.

When the fan shuts off, the vacuum is gone. The small drain tube can't handle it all at once.

Here's the solution: You need a trap near the bottom of the condensate drain line. This will let the line completely fill with water until the fan shuts off - then it will drain.

Some experimentation will clearly be required.

https://www.google.com/search?q=cond...hrome&ie=UTF-8

[Gigler]

Go on the roof and clean the drip pan with bleach and make sure the drain tube from the drip pan under the a/c doesn’t have debris that is being dislodged and clogging the drain tube.

[smgburris]

I'm blown away by all of your kind and informative replies -- thank you all! I am tending to think that the fan is most of (if not all) the issue -- that just makes the most logical sense to me, that the fan pushes some of the condensate away and holds it at bay until it's turned off, then there is a flood of condensate that the drain tube can't handle. I guess the next step would be for one of us to be at the outside drain tube and one of us on the inside under the unit when we turn it off to confirm this. It might not be the definitive or whole answer, but it would seem to be a step toward the right answer. But then, what to do about it?? It's a unit that doesn't have a thermostat, so the fan runs all the time. We've also been told that we shouldn't run the a/c on medium or low at all -- that this actually puts more stress, wear and tear on the motor/compressor than if it's run on high all the time. It's also been so hot here that even on high it can only barely keep it cool. We do still need to try the weed wacker line trick, as well as the shop vac and bleach ideas. My Love says he can't get anything up through the drain tube from the bottom (he'd tried a thin stretched out coat hanger with the end pinched over). He swears there's a kink in the hose (which would be very bad news, in my opinion). When the unit is running, water does dribble out of the drain tube, so we know it's not completely stopped up. I agree that more experimentation needs to be done. It's raining cats and dogs at the moment, and we have a system possibly moving into the gulf coast, so we'll try things as we're able and I'll keep you guys posted!

[dznf0g]

I have never heard that, "only run on high" comment before, and question it. The only times I run on high is during intial cooldown of a hot soaked trailer and when I'm in full sun, above 90* or so. While it.is raining, you could go ahead and pull down the tray from the inside, clean and inspect for cracks.
It doesn't surprise me that your spouse couldn't get a coat hanger very far. There are turns in its routing and wire, not only can puncture, but is too stiff.

[ROBERT CROSS]

^
X2

The vast majority of our AC use has been on the pad while working inside.
I always run the fan on medium or low, and never use the Auto feature>(set to temp), that does make for increased cycling.
Lower fan speeds will increase outlet temps as the air passes slower thru the coils.🤓

On clearing the tube...I use a 1/8"id plastic vacuum tube that hangs out in my tool box 'never throw out' drawer.

Bob
🇺🇸

[GammaDog]

Greetings from Florida where today the humidity reached 106% (not really).

I have had the same issues and slowly worked them out.

First, do you have. Dometic Penguin II that blows directly from the unit (and not through ductwork like a home AC system or the 2015 and newer Airstreams? That’s what I have and can address.

1. Make sure your trailer is level. If it’s not, condensate water pools in the unit, is held in place by the airflow of the fan then rushes out when the fan stops. If yours floods mostly from the street side or curbside of the grille in the trailer, that tells you which side is low.
2. Make sure all three drain tubes are totally clear. Huh? Three tubes? Yes! There are three. There are two short tubes - one from each drain cup - inside the rooftop unit — that join at a tee fitting to the single tube that ends under the trailer (typically in the streetside wheel well). The two short sections and the tee can be accessed by removing the grille inside the trailer. Like Robert, I keep 4’ of 1/4 plastic tubing with an empty dish washing soap bottle on the end. If I remove the grille and pull a line off the tee I can flush all three lines with a vinegar solution from the bottle. My trailer came with a kink in the down line. I had to add 3” of extra tubing. Look for stuff like that.
3. Check to be sure the flexible return plenum is properly secured at each end. It looks like a small cellophane accordion and is at the aft end of a P II. Mine was only connected on one end. The resulting airflow in the unit caused some of the pooling and flooding that I had.

That’s the D P II 101 lesson for today. Post updates if you need to. We offer Masters and PhD programs but pray to God you go camping instead.

Right now I’m camped on the dunes in NE Florida. My AC is turned off. Not taking any chances!

[GammaDog]

4. Make sure the filters are clean. Those are the two trays that pull out of the front of the grille at ceiling level. Just wash them with water to get the crud off.

[DoubleR]

Our 2014 FC 25 FBT single 15k AC had a leak and I found that the nipple on one of the drain cups was broken and we were getting dripping water from that. After doing some research on AirForums and looking at our AC I found that ours only had a single gasket between the roof and AC. I replaced both cups and added another gasket and our dripping problem went away. I was able to do all the repair from inside the trailer by sliding the AC unit around once I removed the inside plastic shroud, four long screws, and metal support.

[dznf0g]

I dont think OP has the cups, unless the unit has been replaced. Older penguins had a tray which is a single long piece. One tube only.

[cwf]

Our 1999 dometic,15k HP (heat pump) leaking condensate..
First it was a “clogged line...which ended up being a cracked “drain pan”..

I replaced pan with cups.. ok.. fixed! Started leaking again...Blew out line then flushed line with bleach and A little dissolved cascade dishwasher powder... Or TSP.. carefully.... I put in garden sprayer into the overboard condensate then tightened hose to the spray tube...minimal pressure Blowing from inside. Remember to protect yourself and throw a plastic tarp Then a drop cloth ..that solution got a lot of gunk out.. caught in bucket outside.

That was good for 6 months..started again when raining.... AC mount bolts loosening and or gasket failing.. bolts were loose. Allowed rain in and couldn’t pinpoint ingress location. Tighten properly... all good.. for a while..

So we chased this problem 5 years.. always something new....

Last summer happened at least leg of trip home. Could not repeat at home when I had time to work the problem...

Enter COVID. WHAT WIILL I DO? I know!!!

Used shop vac from outside to draw debris thru the drain (condensate) tube. Caught tons of stuff in rag over the tube as a filter. Shoot water into drain from top as before.. clean. Used qtip and bent wire to clean “Evap gutter on inside “..sprayed mist of water against coils,, drip rate ok. Blew lines back into “cups”.. drain clean ... so plumbing working.

I then found a major culprit... I missed it for a year. The forward “plenum” has a thin foam insulation glued underneath which is on evap coil air intake the glue/foam failed so foam touched coil and water leaked down, coming out random places depending upon parking level and humidity. It had worsened over time.

Head topside. Cover off AC. Remove screws holding plenum, scrape oof foam off, 3m auto adhesive Sprayed on, Reflective sheet cut to fit Then glued, remount plenum and trapped by the edges by compression. Note the plenum has many “poor fit” which I sealed with aluminum AC and gorilla tape then shot sealant on all edges around bottom of the plenum.ran AC... improvement in airflow!!! So, better cooking!

Ran AC then shutoff.. no water. Not satisfied, went topside and sprayed water all around where it may leak... found another place needing help..kept spraying topside..Water can accumulate in a couple minutes. No leak..shutoff power, water dripping ! Turns out if I run “fan only” before full power down system...2-5 minutes, power off .. no drips.

I then packed rags under the evaporator and shot commercial coil cleaner...what a bunch of stuff came out... flushed rest off coil and thru drain line. ALSO SPRAYED condenser coils FROM OUTSIDE

FLUSH DRAIN THRU THE DRIP PAN! Until clear..

[GammaDog]

^ thanks to Professor cwf! Clearly a PhD holder in Dometic-ology.

[smgburris]

Hello all. Well, we had a major breakthrough in the continuing saga of the leaky a/c. I woke up a couple of days ago thinking about it, and it made total sense to me that the fan running on high could indeed push condensate back, holding it at bay until the fan was suddenly shut off, thus releasing the deluge that the drain simply couldn't handle, thus water pouring into the interior. So -- after Eric had done all that he could do to it cleaning-and-minor-repair-wise, and had carefully put it all back together, we fired it up on high and let it run for several hours. Water was dripping out of the exterior drain tube. Now the test: I first turned the fan down to medium, and waited several minutes. No leak on the inside. Ran outside and water was streaming out of the drain tube! Ran back inside and turned the fan down to low. Again, waited. Still no leaking! Ran outside, and again, water was streaming out of the drain tube! Ran inside and turned the unit off. Waited (I think I might have been holding my breath). No leak!!! Outside again, and now the water had slowed to a steady drip. I was so elated I could hardly stand it! I've done this process now two days in a row, and so far we're still dry. Cautiously optimistic that she's schooled us on one aspect of how she needs to be handled -- this being a new relationship, we're still figuring each other out. Thanks again so much to everyone who took the time to share your thoughts and experiences. We did a bunch of the stuff you suggested, and we know it all made a difference. This forum thing is great, and y'all are awesome!