AC leaking like a sieve

[thomaskemper]

I have been up on the roof and cleaned out drains. I opened the panel inside the cabin and cleaned the condenser. The pan is filling up quickly and leaking like crazy into the cabin. Standing water, just about, on the carpet. No way to catch the water as it is dripping from the entire surface of the cover. Upon opening the entire cover, I found that the water was basically shooting from the duct which provides the air-flow. It reached across the three feet between the duct and my seat-back, soaking the cloth, as well as the carpeting under, to the rear, and to the front of the unit.

Do I have an issue with the top-side condenser? Or... ??

~Thomas

[keymastr]

Youtube is your friend.

Just search for Dometic duo therm maintenance and a bunch of videos pop up.

[thomaskemper]

jetcare wrote:
It would be helpful to know what year or RV you have and if you have a Dometic or Coleman AC. If it is fairly new, the insulation foam will pull straight up and off.

1988 Toyota Dolphin with a Dometic Duo-therm Brisk Air. I still don't know which pad people are talking about. There is a pad, which does lift out easily, which is in the interior cover, so the one in the cabin. When I pull the cover off, inside that cover is a pad. It's fairly flat, and comes right out, although when I just now pulled on it, although it did come out easily, it tore. Seems a bit brittle, for lack of a better word. Maybe old.

[LarryJM]

Thomas,

The evap coil is under that styrofoam cover and mine is an insulated metal shroud as shown in the below pic:



Once removed you will see the evap coil and if you look closely at the pic below of it you can see all the dirt/lint at the very top which you need to clean. You can also see that round "thing" attached near the bottom and that's the anti freeze sensor to protect against frost on the evap coil. The side you are looking at is the "intake side" with the area below open and where the air from inside the trailer is drawn up thru the interior filter. The other side is the sealed portion of the "plenum area" that starts the internal duct work for the A/C. If you look very closely you can just see a white protusion at the very bottom right of the evap coil and that is the drain outlet. There is one on each side of the A/C and there is a tray hidden directly under the evap coil where condensation collect and then drains out and onto the roof.



Here is a pic of one of the "drain outlets) and you can see the open area just below it where the water drains from the Lower A/C pain out onto the roof. You need to make sure those "trays are clear and you should be able to use something like a turkey baster to try and fill the pan below the evap and see if that drains out thru those trays.



Larry

[jetcare]

It would be helpful to know what year or RV you have and if you have a Dometic or Coleman AC. If it is fairly new, the insulation foam will pull straight up and off.

[chuckklr04]

Mine did the same a little. Cleaned the coils today. Took off the metal shroud covering the top of the front Evap coil, and found a bunch of mud daubers nests. Cleaned them out due to the mud droppings on the pan blocking drain.. Coils look like new now! my little 7180 btu dometic is gonna cool like crazy now, and be dry inside.

[thomaskemper]

jetcare wrote:
The front coil is called the evaporator coil and the back coil is the condenser coil. The air in the RV is pulled through the evaporator coil and heat is pulled from the air and then cool air is returned to the RV. Are you sure you have checked the tray below the evaporator coil and know for sure that the drain holes are clear.

You should be able to pour a quart or two of water onto the top of the evaporator coil and see it run down the evaporator, then out the drain holes and then on to the roof. If the evaporator drain pan fills up with water, it then overflows and water drips out of the ceiling assembly and into the RV.

OK, this is the most help to me at this point, but I have a question: obviously, I can't access the drain-pan from inside (except to stick my fingers in to feel that it is full of water), so I am assuming I have to disassemble the shroud which covers the evaporator coil to access the drain-pan. But when I went up the first time to inspect the unit, I found that it is covered with an insulation pad (like dense styrofoam), and I don't see how to remove it. Of course, I wanted to inspect everything, but this is something I could not figure out. I will go up again and give it another go using your advice. I will check back when I finished, and let you know what I encountered.

Thanks.

~Thomas

[jetcare]

The front coil is called the evaporator coil and the back coil is the condenser coil. The air in the RV is pulled through the evaporator coil and heat is pulled from the air and then cool air is returned to the RV. Are you sure you have checked the tray below the evaporator coil and know for sure that the drain holes are clear.

You should be able to pour a quart or two of water onto the top of the evaporator coil and see it run down the evaporator, then out the drain holes and then on to the roof. If the evaporator drain pan fills up with water, it then overflows and water drips out of the ceiling assembly and into the RV.

[Matt_Colie]

Matt_Colie wrote:
Many RV A/C units draw through the evaporator. When the unit's internal filter gets too clogged, the fan starts to draw air in through the drains so water can't drain out. So, it comes in with the air...

Matt

thomaskemper wrote:
Is this a filter up top or inside?

Matt_Colie wrote:
Thomas,
Most are in the inside cover and are easily removed. In my Carriers, I can pull them out and bang them on something to clear them.

Matt

thomaskemper wrote:
When you say inside the cover, do you mean inside the shroud up top, or the unit cover inside the cabin? There is a removable foam pad in the unit cover that looks a little flat, but I have never seen an original (and can't seem to find one online), and so I don't know what they are supposed to look like.

Thomas,
I am stretching some memory over many years, but all of the units I have had did have the filter installed in the inside cover. Some took minor disassembly to access, but all did have them.

One, and I have forgotten which, came to be real bad and was a massive PITA to service. I had to remove knobs, then 4 screws and disconnect things to get at the filters that were so clogged that they really didn't clean well. I replaced them. In a later discussion with a friend of the PO, I found that the though of replacing the roof A/C was the reason he sold the unit so cheap.

Matt

[hotpepperkid]

The drain it plugged or partly plugged been there don't that.

[thomaskemper]

Matt_Colie wrote:

thomaskemper wrote:

Matt_Colie wrote:
Many RV A/C units draw through the evaporator. When the unit's internal filter gets too clogged, the fan starts to draw air in through the drains so water can't drain out. So, it comes in with the air...

Matt

Is this a filter up top or inside?

Thomas,
Most are in the inside cover and are easily removed. In my Carries, I cam pull them out and bang them on something to clear them.

Matt

When you say inside the cover, do you mean inside the shroud up top, or the unit cover inside the cabin? There is a removable foam pad in the unit cover that looks a little flat, but I have never seen an original (and can't seem to find one online), and so I don't know what they are supposed to look like.

[wa8yxm]

Ok, you said you went topside and checked the drip tray and drain lip, they are clear.. did you check to insure the water is driping INSIDE the A/C and not running in off the roof (Easy way, Dump a bucket of water all around the A/C tossing toward the A/C and when A/C is not running

if water is dripping inside three options

As someone suggested raise the front an inch or two.. This makes the front lip higher and just an inch or two won't bother the fridge.

Two: Clean the intake filters (alsao suggested avove) as if they get dirty the blower will such water out of the tray into the area in front of the condenser and then when the fan shuts down NIAGRA FALLS, it may drip for a while before that.

Finally. Cracked drip tray. Repair or replace. (Foxy-Poxy, and underwater epoxy designed for use on swimming pools MIGHT work.

[MrWizard]

That "foam pad" is the a/c roof gasket
Replace it, all roof units use the same size
Do Not tighten as tight as you can, do not Flatten the gasket
It should only be compressed to 1/2 thickness when installed
Remove and clean or replace the air filters, they are on the inside under the the return air grille

[Matt_Colie]

thomaskemper wrote:

Matt_Colie wrote:
Many RV A/C units draw through the evaporator. When the unit's internal filter gets too clogged, the fan starts to draw air in through the drains so water can't drain out. So, it comes in with the air...

Matt

Is this a filter up top or inside?

Thomas,
Most are in the inside cover and are easily removed. In my Carries, I cam pull them out and bang them on something to clear them.

Matt

[thomaskemper]

jetcare wrote:
Would you be able to provide the model number of the AC and what kind of RV you have? I would take a close look at the return filters. These are the foam filters that let RV air back into the air conditioner for additional cooling. Then the cooled air is returned to the RV through the ceiling ducts.

It the water dripping from the ceiling assembly or the ceiling vents?

Is it in the cover to the unit? My motorhome is a 1988 Toyota Dolphin, but I don't know the model number. Would I find that on the unit?

Water is coming from the duct that runs up to the blower, and it's also collecting in the pan below the condenser. Not coming from the vents at all.

There is a foam pad inside the cover that is pretty flat. I'm guessing that needs to be replaced, but that may be a separate issue. I don't know because I know next to nothing about these things. I've learned a thing or two, for sure, but not that much.