Alde leak...could use some help

Todd77

Hey folks, I am moving into winter here in the NE and I just discovered that my Alde reservoir isn't holding the glycol and therefore my heating system doesn't work.  I have not been able to find where the fluid is going as I do not see any pooling anywhere.  Does anyone know where the leak maybe coming from?  I am hoping to solve this before the temps drop below freezing!!  Thanks! 

ScottG

Is there evidence of glycol having leaked onto the floor of the camper behind the Alde? Cracks in the bottom of the plastic reservoir have been responsible for several such leaks noted in the past. I'd check there first.

Also make sure the metal plug is still in place in the Alde glycol drain that exits to the outside behind the driver's side wheel.

Todd77

I'll check these out.  Thanks Scott!

Todd77

Well, I found the leak.  It is underneath the tab which is why I could not find any pooling within the unit.  It is going straight out of the tab onto the ground.  Anyone know how to fix this or what parts I need get and where?  Thanks!

Todd77

I'm guessing that I just need to find a way to plug this output hose, but as I look closer there maybe a leak happening above where the hose leaves the trailer.  There seems to be some moisture around the hose as it leaves the trailer.  

ScottG

Looks like you are onto something.

Note that there are two locations where glycol may come out from underneath the trailer. One is the actual glycol drain, which tees off of one of the heavy black glycol hoses the Alde compartment. Loss of the metal drain plug would obviously cause complete loss of glycol from the system.

The other is the glycol reservoir overflow. This is a clear plastic tube that threads from the top of the reservoir out through a hole in the floor. Over time, glycol can splash out of the overflow and trickle away. I had to add a bit this year for presumably that reason.

If you trace where the two hoses exit the floor of the Alde compartment, you should be able to determine which one is showing the leak. In any case, one of the myriad hoses sticking out under the T@B should have a metal drain plug in it. I know there is a photo kicking around here somewhere, but I don't have quick access to it.

Cbusguy

Not sure I would simply plug it as it could be a safety relief valve.   Track it back and replace the offending valve be it a drain or relief valve

Bayliss

@Todd77, I believe that @ScottG is referring to the glycol drain, which is "E" in the photo below.  Check to confirm it is capped/plugged/closed with a metal or plastic plug.  If not, your glycol will drain out of the holding tank.

The three tubes that go through that larger black pipe depicted in your photos are overflow/pressure relief tubes, (e.g., when the glycol tank is too full, or the hot water tank has too much pressure.)

What is of interest to me is that, if I see what I think I see, it looks like there is wet areas around the large black tube (i.e., the area around that tube is damp.)  When you look at the Alde compartment inside your camper, is it wet around that tube (the one that has three tubes going through it), or has one of the three overflow tubes popped out of that larger tube?

ScottG

In the case of the Alde, I'm almost certain the glycol drain is a simple plug. System glycol pressure is relieved through the reservoir/expansion tank and its associated overflow hose.

Todd77's photo looks more like the tank overflow exit rather than the actual glycol drain (which should be plugged) but its hard to tell for sure without seeing the whole picture.

Todd77

Here are a couple more photos.  Not sure if they add anything to the discussion.

Todd77

So is the hose that is leaking the glycol missing a cap at the terminus, or is there a valve "upstream" somewhere that may be damaged/missing?

Todd77

and here is the top side.  Looks like there is glycol in one of the tubes still.

ScottG

Those photos are helpful. The upper hose in the second photo looks like your system glycol drain--which is still securely plugged.

That suggests the location where you identified the drip is your reservoir overflow. That line should not be plugged, and a little drippage from that location is not out of the ordinary under normal circumstances. I doubt it would empty they glycol from the entire system unless something else were happening. There is no valve or other device controlling the overflow from the reservoir.

So... a mystery still. Going back to your original post, are you certain you are out of glycol? What exactly happens (or doesn't happen) when you try to use the heat? 

Bayliss

@Todd77, your first photo is a propane connection (tees off in two directions.)  Second is glycol drain with red cap/plug.......looks OK to me.  I don't see any sign of leakage in third photo around the tube that allows the three pressure relief/overflow tubes to exit to outside the camper.  Therefore, I still wonder why it is damp around the exterior of that black tube on the underside of the camper.

Are you sure it is not leaking at the Alde glycol tank/reservoir itself?  Probably not, but worth re-checking.  If it is currently empty, I would suggest refilling it and see what happens.  Maybe do that and then run the Alde so the glycol heats up.  Maybe the glycol is getting too hot and is overflowing through the overflow tube?

ScottG

Todd77 said:

and here is the top side.  Looks like there is glycol in one of the tubes still.
...

Yep. The lower tube in your last photo is your glycol reservoir overflow, and it looks exactly like mine. Normal bumping and thumping down the road will pitch a little glycol down that tube, but that won't explain the system completely draining itself.

Todd77

I have had to refill the glycol reservoir twice recently.  The first time I assumed the glycol just burned off after not being used for awhile.  I refilled it and ran the system and after a day it had emptied again.  Possibly two days.

Cbusguy

Refill it and run it and watch all the connections. 

 I wonder about adding a bit of radiator leak detector to the system.    Uses a uv dye and associated flashlight to find difficult leaks.  You would need to flush it good after repair. 

Todd77

I just refilled it and I am going to see if it leaks before I turn on the alde.  The previous glycol that I filled up the reservoir with has pooled up on the "card board" material used to create the black undercarriage of the Tab.  I think it came out of the larger diameter tubing from the first picture, and hit the framing which gravity sent to low points along the undercarriage.  Not excited!

ScottG

Well, I've added maybe a half cup or so of glycol to my reservoir in five years, so burning off is not likely the issue.

Which still leaves the question of where it is going. If the drain plug is still in place that is not the root of the problem. It could be getting forced out the reservoir overflow, but I'm not sure what could cause that to happen so quickly and completely. Otherwise, there's got to be a pool of the stuff somewhere.

Roughly how much did you add when you had to refill? I'm still trying to ascertain if your system is completely empty or if it's just your reservoir.

Todd77

It is pooling up outside of the trailer on the ground and in part under the undercarriage as I mentioned above.  The reservoir goes completely empty after the system is on for awhile.  I have refilled it and the system is not on yet, as I want to see if it is a plug/valve issue first.  In an hour or so I will turn the system on and see if it is a pressure issue and possibly where the glycol is being forced out.  It has to be towards the terminus of the tube though as there is no evidence of glycol pooling up internally in the Tab.  Mystery for sure!

ChanW

Turning it on might help get the glycol circulated into all the hoses, but it's not a pressure system, it's all at atmospheric pressure (your reservoir is vented to the atmosphere).

Any signs of leakage on the floor underneath the reservoir? Might it be leaking from the reservoir and going underneath the floor through a seam in the flooring before it pools?

ChanW

Also, I'm wondering what that black material is on your floor. Ours sits directly on the 'wood' flooring as shown in in Bayliss' 2nd photo. Is that material hiding your 'pooling'?

BrianZ

Just a couple of thoughts..
It seems to me that if the system is low on glycol, the best time to check & add more might be when it is still hot after running for a while, then turn it off & add to the expansion tank so it can suck it back in as it cools.  If it sucks it all back in, then you might need to repeat adding/cooling.  I just went through something similar with a car leaking coolant.
Also, you might want to check to see if you can detect whether the Alde circulation pump/fan is working (including fuses on top of Alde).  Maybe you can hear or feel it.  Some have a switch on the pump with speed settings too.

I seem to recall that someone once said that setting the speed too high could make the fluid bubble up & overflow from the expansion tank.  I believe a low setting like 1 or 2 is normal.  And if the pump is not circulating the glycol to dissipate heat, then maybe it could overheat it & blow some off via the overflow tank?

falcon1970

If you are using Century Transfer Fluid (and you should be) it will fluoresce under ultraviolet light.  Lowe's carries a Craftsman UV flashlight.  This makes it easier to track down leaks.  Also very handy for checking the fluid level in the reservoir.


  

Cbusguy

I had no idea thx falcon......I suggested adding leak detector earlier in the thread.

N7SHG_Ham

Very common for the hose bib where the black hose connection is on bottom of reservoir to fatigue crack and leak.

Sharon_is_SAM

@Todd77 This fall we had the flow assembly unit (A in the above photos) replaced.  We were having to add too much glycol and we noticed glycol residue on the flow assembly.  The Alde rep explained that it is part of the auto air bleeder system.  It has a one way valve and if the float gets stuck, the valve remains “open” and the alde will push out glycol instead.  This may be the source of your problem.  Austin at nuCamp said that he was seeing more of these issues with the flow assembly.  To repair it, you need to drain the Alde (mostly done in your case), remove and replace the flow assembly, then refill and bleed the system of air.  Kind of funny, the Alde rep said to give the metal flow assembly a couple hard wacks to try to unstick the valve float.  We tried that without success.  

Tabaz

Falcon 1970 - thanks for the UV light info!  Todd - all Alde hoses, connections and components are located above the floor of the trailer (i.e. in the cabin).  You say you have a leak on top of the coroplast plastic undercarriage covering.  This means to me you have a leak somewhere inside the cabin that is dripping down into the "basement" of the trailer.  Every Alde hose and connection can be seen from inside the cabin if you remove the pedestal seat cushions and rear wood panel at the back of the trailer.  Using Falcon 1970's suggestion of a UV light should help find the leak.  2015 and 2016 models are prone to breakage at the nipple at the bottom of the Alde resevior tank.  Happened to me.  Good luck!

ChanW

To test if it's the auto air bleeder 'flow assembly' that @Sharon_is_SAM referred to, you could temporarily stick the end of the clear hose that's attached to the bleeder into a container to catch the overflow. If it's leaking that badly, it would accumulate pretty quickly in the container.

I'm still betting on the cracked reservoir nipple, however...

Bayliss

@Todd77, if it is not leaking at the Alde glycol reservoir/tank, you should find and check the bleeder valve/screw.  It is located at (at least) one point in the glycol rubber hose that circulates throughout the inside area of the camper.

It appears that you have a T@B 400, so I am not sure where yours is located.  On the T@B 320S, it is located inside the rear storage area at the far rear passenger side corner.  It is in a bend in the rubber hose (just as depicted below) and not far from the rear convector (the metal fins that look similar to a radiator.)  It could be loose and leaking glycol.  If so, the glycol stain should be very evident in that area, but it looks like you might have that black flooring option (I can't recall the name of it), which may make it hard to see a leak.  Regardless, if the bleeder valve/screw is loose, turn it clockwise to tighten.

The valve/screw may be hard to see if it is tucked away, but look along the black hose on either side of the convectors.  Maybe someone with a T@B 400 can help with where it is located.

P.S. @falcon1970, GREAT tip re the UV light!  That would really help in locating a glycol leak on dark flooring.

P.P.S.  @Todd77, take a look at the following thread.  It is a discussion about the flow assembly mentioned by @Sharon_is_SAM.

https://tab-rv.vanillacommunity.com/discussion/comment/117156#Comment_117156

Tabaz

BTW, the failure at one of the two bottom nipples on the overflow tank is probably caused by the factory not installing a 90* elbow at one of the hoses.  Mine had a kink in it which put strain on that plastic nipple causing it to fail. You can see this by removing the wood board over the rear cabin area and looking at the hose running from the Alde heating convector to the overflow tank.