Alde Glycol fluid empty

loganphotos

I have a 2019 TAB 320s boondock. Since Covid started I have used the camper on my property a couple nights a week. The heater is used relatively heavily for the last couple months (3-4 days a week). This is the second winter season for me and I imagine it is around the two year mark for a fluid change anyway.

So here is what happened recently. One night after running the Alde for about a day it stopped heating. I shut down middle of the night and the next day noticed the fluid was empty in the reservoir. I inspected the interior everywhere and couldn't find any sign of a leak. I ordered a gallon of Century Transfer Fluid and put about 2/3 of it before it seemed to top off at the max mark of the reservoir. Heat returned to normal for a day, probably 12-14 hours, then stopped heating. The reservoir is empty again. I did open the bleeder valve briefly and some air escaped prior to topping off. I have shut down again. I have noticed a small amount of fluid outside under the drip drain. Not the drain plug but the 1" overflow drain (not sure if this is the correct name). It is possible that a significant amount drained out as it is just dirt underneath the camper but I have no way of knowing.  

I did notice that the pump was set at 6-7 which is high. Is it possible that that much glycol was pumped out and or evaporated? That doesn't seem likely but I can't find anywhere that it would have leaked from. I will be doing a complete search of the glycol lines this week but I wanted to see if anyone has faced this issue. Thanks. 

pthomas745

Have you looked for a puddle under the trailer?  It has to have gone somewhere, and out the drain on the bottom is possible.

loganphotos

There was a small amount of glycol under the drain. I'd say a couple ounces visible on leaves and debris. Not really a big puddle but it did rain a bit and may have washed away the puddle. I suspect it came out from this spot but I don't know why that would have happened. 

Verna

I had that happen once on my 2014 T@B S Max. It emptied the reservoir, out the drain. I filled it, but only to the minimum line. It never happened again. I figured it just belched, got rid of some air and it felt better afterwards. I had it for another two years and it never happened again. 

loganphotos

Thats exactly what I'm hoping for. It's like the second time I filled it up it had air in the system and so it only took half a gallon. I originally thought it wasn't empty. I have ordered 3 gallons and will do a complete drain so we will see. Thanks.

Sharon_is_SAM

Turn down the pump to 1.5 to 2.  Excess churning can lead to glycol loss.  See if this fixes the issue.

Another issue is a valve on the Alde that gets stuck open, allowing glycol to leave the system.  

loganphotos

I will definitely keep it under 2. Which valve gets stuck open? I can't seem to locate anything that looks like it be open.

ChanW

The only valve I can think of (that @Sharon_is_SAM might be thinking of) in the Alde glycol system, would be the automatic air-bleeder valve, in the Alde compartment. A brass fitting on the black rubber glycol line that has a clear plastic hose coming off of it, which goes down to drain through the floor. 
Look under the Tab at the hoses coming through the floor to see which one has a bit of glycol dripping off of it.

Sharon_is_SAM

@loganphotos - as Chan described, here are photos of the Flow Assembly (A) with the automatic air bleed valve.  That valve is internal and gets stuck open allowing the glycol to escape through the attached drain tubing.  In this picture, it looks like the drain tubing is black, but I think our TaB’s tubing is clear.

Bclarke

Help!   I have a 2021 320 S     It is parked on my driveway on shorepower but I am using the Alde on propane.  The past few days I noticed my glycol was empty.  I filled it yesterday (just below the max line) and it is empty today.  I checked in and around the Alde compartment and also under the camper by the red bleed valve.  Nothing.  I did notice however fluid in around the glycol tank itself and in particular around the cap.   My cap doesn’t fit tight (if you tighten it just sort of pops off and is loose again) so am wondering if pressure isn’t forcing it all out?   There is some minor splatter on the pipes around the glycol tank as well.  For the life of me I have no idea where the fluid is going.  The drive is gravel and I have no sign of fluid on the ground. I thought about adjusting the Alde pressure but cannot find the settings for that.   Help?  

Denny16

Given that your 320 may still be under warranty, I would contact your dealer, and have them check it out.  You could also put a call into nüCamp’s service department for their recommendation.  Aside from the obvious points of a leak already mentioned, it is hard to diagnose this type of issue second hand.  You could try putting a fan or container under the Alde drain tube, to be sure the glycol didn’t come out of the valve.  Also a good tap on the valve head, might get it unstuck, if that runs out to be the issue. 

 

Also, if you haven’t previously used the Alde much, the fluid loss might be down to previous air in the Alde lines getting purged out.  I noticed this when we had the fluid changed in our TaB last spring, and I had to add glycol twice, to top the system off.  Now it seems to be maintaining its level.

The mid point between the two marks is the approximate level when the Alde is hot and running.  The lower mark is the cold Alde fluid level, from the Alde recommendation I have read.  The glycol expands as it is heated.  Also, the glycol expansion tank has an overflow drain hose on it, you might put a contain under to check it for an overflow leak.  

Lastly, one previous TaB owner reported having a crack in their reservoir/expansion tank, and the fluid leaked out.  Use paper or a cloth under the tank to check this out.  Spilled Glycol is hard to see, it does a good job of blending in and flowing away.  You can remove the tank for a better examination.

cheers

Bclarke

Thanks @Denny16. Unfortunately I am parked in Montana… Getting ready for our trip back home to Illinois next week. Needless to say I need to rely on a little bit of heat while traveling. I will put a call into new camp tomorrow as you suggested. Frankly I’ve never liked the fact that my cap doesn’t tighten.  And a great suggestion to about putting something under the relief valve. I don’t suspect that’s it… Because I did find fluid around the cap and on some of the adjoining pipes this morning. I wiped all of these down yesterday so I know there was no liquid there then.

Denny16

OK, good luck, safe travels going back home.
cheers

Bclarke

I think I see where it is coming out… the overflow tube has moisture in it and explains how glycol was on the top of the tank lid. But seems very odd that it would force it all the out of this tube and empty the tank. 

Sharon_is_SAM

@Bclarke - this thread has a picture of the Alde pump control.  Set it no higher than 2.  I agree with Denny - air may be a factor as well as churning.  

Bclarke

Well… unfortunately (or fortunately) it is already set to 1.   Sigh… 

Sharon_is_SAM

How full was the tank?  I would fill it up and put a pan under the Alde glycol drain.  

Bclarke

For the last few weeks it was about 1/3 between min and max.   Yesterday when I noticed it was empty I went to max.  Today I refilled to just above min to see what happens. 

Denny16

Yes, max is too high when cold, and would explain why glycol came out the air vent tube you circled above.  Stay with the bottom mark for a cold level and half way when hot.
cheers

Bclarke

@Denny16 @Sharon_is_SAM I always so appreciate your help.  Fingers crossed that it was just a matter of being too full.   I have a pan under the drain just in case. Stay tuned!   

Denny16

@Bclarke did you check your circulation pump setting per Sharon’s recommendation, to make sure it is not set to high?

cheers

Bclarke

@Denny16 yes… photo above.   It is set to “1” 

ScottG

If you can't locate a clear leak, I second the explanations that to loss is result of splashing from the vent/overflow, and perhaps air pockets working their way out of the system and causing the glycol level in the tank to drop. The Alde glycol loop is not under any pressure, so under normal circumstance there is nothing to force glycol out of any of those openings.  

BrianZ

Also check to make sure the brass-colored air bleeder assembly at top of he Alde is level (hose rests on a plastic support to help keep it level.  If not level, it can push out some glycol, which is likely worse at higher pump speeds.  It drains to the ground under the T@B.

tybladesmith

@Bclarke, The circled hose is the breather hose, the other hose coming from the near side of the reservoir is the overflow hose. I would recommend having a pan under the outlet of that hose the next time you need to add PG to the reservoir. The automatic air bleed hose also drains under the T@B which can complicate diagnosing the source of PG loss. The auto air bleed valve can get stuck open with debris.
Adding a tight turn or two of electrical tape to the neck threads of the reservoir can tighten the fit of the reservoir cap if it is loose.
There is no adjustment for pressure. The Alde system operates at atmospheric pressure through the circled breather hose. 
Speeding up the circulation pump should move any trapped air to the reservoir and auto bleed valve. Always turn the speed back down to 2 when done servicing.
I think the 2021 320S has more Alde piping than earlier models ie. reservoir behind the toilette, and maybe more difficult to (burp).
It takes these types of issues to begin learning the Alde system. You will prevail!

Bclarke

@tybladesmith I have so much to learn!  I have been watching the level for the past few days. I filled it to the Minimum level.  Yesterday it was up to the Maximum level… obviously a lot of fluid was in the lines when I filled it.  I appreciate your explanation of the lines. What is odd is that there was fluid around the tank cap and on top of it too.  Will continue to monitor.   Thanks 

Bclarke

Ok… so here is my update.  First, forgot to mention that I am at 5200’ (I know it matters from a propane perspective).  A few days ago the glycol was at the “min” level .. the next day I noticed it was at the “max” level (presume the difference is glycol running the lines or not?). Today … the tank is empty. And because I was ready for it I noticed that it all leaked out the bottom under the tank on the ground  - through the overflow tube I presume.  The Pump is set at “1” as well.   What am I doing incorrectly?

Denny16

I suggest taking your TaB to a dealer and have the fluid CHP’s get and the Alde system checked out.  Your bleeder valve could be stuck open, allowing the fluid out the bottom.
cheers

Sharon_is_SAM

Have you been running the Alde while trying to diagnose this problem?  If so, was it heating the cabin?  I ask because if it was just a stuck open air bleeder valve (which inadvertently allows glycol to drain) you would not see glycol appearing on the reservoir cap.  It almost sounds like there is an obstruction preventing forward flow.  Usually that is a big air block.  Hmmm...

Denny16

Good point Sharon…
cheers

BrianZ

Try tapping on top of the brass air bleeder valve with the handle of a screw driver to see if that corrects the situation.  There is a floating disc inside that can get stuck after letting air out, and this might fix it.