Glycol level in expansion tank

Sweetb

2021 320S . We’ve only used Alde briefly shortly after purchase, mainly to verify it worked properly for cabin heating - which it did. The glycol level at that time was between the min/max markings as per operating instructions. We camp mainly in Florida and have not needed to use the heat. Recently on return from a short trip (where Alde was not used), we noticed glycol leaking from overflow tube on the expansion tank. The glycol level was above the max level - no additional glycol had been added since it was last used. We tried manually bleeding with minimal results. Leveled the trailer and ran the Alde at a higher pump setting (as recommended in several forum resources). Unit appeared to work correctly and glycol level returned to original point slightly above the minimum mark. Two days later - glycol level is again above the maximum level. Any input on why this is occurring? Thanks.

MuttonChops

On delivery my Alde expansion tank was well over the MAX level.

After a few outing it settled down to something between Min & Max

I assumed this was a function of air in the system.
I just let the installed 'automatic' air bleeder to do its job.  After a number of Adle uses the expansion tank level stabilized.

Sharon_is_SAM

Good question for Help@nucamprv.com.
Very odd that it returns to a higher level when cold, level and not in use.  If that happened while heating, I think that suggests an air lock, but I can’t see this happening when cold and the pump turned off.

Denny16

What has been your air pressure changes.  The Alde glycol tank level will change with atmosphere pressure changes, with the air vent tube allowing the pressure to increase or decrease in the expansion tank.
 Cheers 

Sweetb

Typical west coast Florida weather for this time of year. Temps are still in the 80’s ( low 70’s overnight ). No storm systems for days in our local area. Currently being stored at home in same location as last fall. Did not experience any “known” glycol level changes in the past …at least none were observed that resulted in glycol being expelled through overflow tubing. 

Denny16

This happened to me last fall after I topped off the level to mid point, then low pressure front came in, and the glycol pushed out through the overflow tube.  Ran the Alde, level came back down.  I am not sure of the pressure change had anything to do with this, but it has been OK since.
 Cheers 

Sweetb

Still have not gotten an accurate “diagnosis” of the problem. However, it has been determined by the NuCamp warranty division that we are eligible for the flush and glycol exchange (from Century to Rhomar) under warranty. We have an appointment in early December with a local NuCamp dealer. Service department assured me they were familiar with the Alde and equipped to do the exchange. However they were not aware that NuCamp authorized this service for certain models based on manufacture date. He’s checking into it so hopefully that will be clarified by the time we roll up. They will also check into the mysterious glycol level fluctuations at that time. 

bergger

If for some reason the dealer says you have to pay for it just keep your receipt then contact NuCamp and they will reimburse you.  We were authorized for the exchange as well but I did it myself prior to that notification.  NuCamp just asked me to email the receipt for my materials cost and they sent me a check.  Also if the dealer does it I would double check it prior to leaving to make sure the glycol is the proper color and has not been mixed with the old century.  Stress to them the need to push at least 15-20 gallons of water through the system and bleed water out of all bleeders prior to introducing the new Rhomar.