Glycol leak

jschmier

There is a large leak of antifreeze on the rear passenger side of my 400 behind the wheel well.  Even with pump off, it leaks as soon as I fill the reservoir. I checked the registers and piping behind the bed and everything appears Ok and feels dry. I have not found any glycol in the interior of the tab, the storage compartments, or near the Alde itself but can see it dripping along the bottom rear side when outside the trailer.  Any ideas.  I was thinking about pulling the frig to hopefully find the leak.  Any other ideas?

pthomas745

What year 400?  Confirm you are talking about "outside" the trailer?

jschmier

It is a 2018.  I have attached a picture. It leaks along the bottom edge and is heaviest nearest the wheel but the bottom trim is also angled downward so it's hard to tell where the leak originates.  I was hoping not to have to pull the bottom cover which means taking off the stabilizers yet not know if I will be able to see anything.

bergger

Is it coming from the glycol drain tube?   It's the black tube with the red plug in it that protrudes from the underside on the drivers side of the trailer..  Check that and see if the plug is missing or maybe has gone bad. 

pthomas745

Your drains are over on the driver's side, as Bergger points out.  So, go over to that side and have a look underneath and look for them.  The other place the glycol can drain like this would be from one of the hoses that go out through the floor near the Alde compartment.  Some owners have found the Alde "auto air bleed" valve decides not to be "auto", and air blocks the glycol, and it escapes through one of those hoses.

Have a look at this thread:

https://tab-rv.vanillacommunity.com/discussion/12879/empty-expansion-tank-and-glycol-all-over-the-driveway/p1

jschmier

The glycol is not coming from the drain tube; checked that first. If the bleeder valve is stuck or faulty, could antifreeze show up on the other side of the trailer even though I don't see anything on the inside?

pthomas745

The only place the glycol could exit the trailer without there being some catastrophic leak in the expansion tank, a convector, or hose, would be through the clear drain "tubes" or from the capped off glycol drain.

The "coroplast" cover may only need a couple of screws to be removed from the edges to allow a peek under there. It is kind of hard to see, but in this thread you can see a picture of the "rail" edges with screws that hold the plastic on, and then the fender bolts toward the middle that support it.  The "rails" you should be able to spot all around the outside edges of the bottom of the trailer.

https://tab-rv.vanillacommunity.com/discussion/12820/had-leaking-inside-first-time-using-black-tank-flush

XenanMe

You might want to check if you have an Alde bleeder valve behind the sink area.  I know my 2018 400 has one back there.  I can’t reach it but it is visible using an endoscope camera that I bought off Amazon.  Either that or something might have damaged/loosened the Alde lines to the convector behind the sink/stove counter.  The camera is the easiest way to see what is happening back there without taking the cabinets apart.

1985Tiger

Oh my! 

I have a 2022 TAB 400 and have the same issue of Glycol leaking out of the rear passenger area behind the wheel well -- same as JSCHMIER (https://tab-rv.vanillacommunity.com/profile/jschmier).  The glycol appears to be between the trailer flooring and the coroplast.  I checked all over inside and found no evidence.  I also pulled the bottom drawer out under the stove (NUCAMP Tech advised me to check that elbow fitting) and no leak there either.  Further no leak visible inside the trailer or in the ALDE Heater compartment.

I ready to pull the "coroplast" but wanted to find out what JSCHMIER did to resolve the problem.  Wasnt clear in this text string.  

Help!?

DM159

Our 2022 TAB 400 had a very similar leaking issue.  No evidence on the floor anywhere I could see (behind and underneath) on the inside of the trailer.  All the glycol leaked from the front of the left wheel well onto the ground.  Turned out it was a failure of the interior Alde tank weld.  Have you registered your Alde serial number with Truma for a potential warranty claim?  

1985Tiger

DM159
Thanks -- I did register it, thanks.   I 'think' I found the leak in one of the bleed lines.  Very very slow drip but since I had the unit almost a year, it might be the cause....I sadi "might" as I posted some pics.  

I see no evidence of a leak in/around the unit itself so if it is the tank, how would it leak beneath the camper flooring?  I'm curious on how you found your leak led to be the interior tank weld?  Does the unit have a bottom drain?

I ordered some more glycol to add.  The tank is almost empty.  I'll check it again and check for leaks.  I'll even call the Truma tech....the NUCAMP Tech told me they didnt like advising DIYers.

Still a head-scratcher.  Help and counsel is appreciated here.

1985Tiger

First one showed the leak, the second shows the wall where the leak dripped.  When I wiped it, the leak continued.  I assumed it leaked down the wall and underneath the flooring over time.
.

DM159

Glad you found a potential leak.  Looks like it can be repaired.