Alde Circulation Pump Stalling

Moabyte

I recently purchased a late 2015 320S with a few known problems.

I knew I had an Alde problem; there was no glycol seen in the reservoir. I took it to an Alde service center 100 miles from home and they found a broken reservoir (good troubleshooting). They were searching this forum for how-to info. I had asked them to use the newer glycol mixture recommended by Alde. They knew nothing about it (only had Century) and said the changeover was only necessary on 2018 forward according to this forum (???). I believe nuCamp was only exchanging the glycol for the newer T@Bs because they were responsible for those warranties. Having no confidence in this service center I took the trailer back home and ordered the spare reservoir through a nuCamp dealer 500 miles from home and subsequently took the trailer there for Alde service. They installed the reservoir, exchange the old glycol for the Rhomar. They left the trailer dirty, tools were strewn inside (I had to return them), This cost me over $1,000; again I was not too happy with service.

Once at home the circulation was very noisy. I learned from the forum I could reduce the noise by turning down the pump speed to 1-2. I do have the manually adjustable circulation pump. They had left the circulation pump on 5. I assume they had left the pump on high speed to purge the air and failed to reset it.

I then began to check out the Alde functions. It heated hot water and the cabin on shore power and circulated throughout the radiators. I began to try the same for LP. At some point the circulation pump began to make a noise: a hammering (not very loud; sounds like marbles rattling) for about two seconds, a two second pause, and then hammering, etc. Could it be debris in the pump? At one point this behavior cleared up but then returned several minutes later. I disconnected the circulation pump from the Alde and applied 12 V directly to the pump leads and found the same behavior. The pump would again draw about half an amp for a second beginning to spin, then rattle and perhaps stall drawing 1.25 amps for a second, then would drop to zero for two seconds and then repeat. Is there a small circuit breaker built into the pump itself? Is there any kind of strainer in the glycol system like in the fresh water line that might show debris? Do I have debris in the circulating glycol that periodically jams the pump? I have no external evidence of aluminum/glycol corrosion in the system.

Right now I’m at a loss for what to do without doing something major: remove and replace the glycol? Remove glycol and pump to check the pump? Since I won’t be changing glycol brands I just have to drain enough to open the system, not drain it completely.

I’m not sure I want to try the next further service center….

pthomas745

Don't be too hard on the dealer as far as the glycol goes.  Unless they have been able to keep up with the steady flow of information from the hundreds of comments in threads that have been in existence since 2016, it is easy to fall behind.  There is a lot of misinformation out there.  Congratulations for recognizing they may not be completely up to speed, however.  (There is no excuse for the second center's sloppiness.)

So, you turned the pump speed down? And the pump is still making noise?  There haven't been too many pump failures over the years, and it is hard to find examples of owners who have replaced them. 

There are, of course, videos on how to remove and replace the pump. 

https://www.youtube.com/watch?v=-8ECvhAiTEY

Sharon_is_SAM

@Moabyte - I thought about the possibility of residual Century glycol before the Rhomar was added. Alde warns against mixing the two glycols, but did not share the possible reaction.  Also, how long was the broken reservoir exposing the system to air, did any glycol dry out leaving debris in the system?  Will the dealer share how they exchanged the glycol?

Before you change the pump, I would contact Alde and run your scenario past them. 

Alde / Truma 

Telephone:  (877) 860 9814

Alde E-mail:  service@alde.us

Truma E-mail:  service@trumacorp.com

Moabyte

I will try contacting Alde/Truma as suggested.  Sometimes it will work for a day or two and not malfunction. Sometimes it will malfunction for a day and needs to rest for a day before recovering.  Manually changing the pump speed neither makes it work correctly or causes it to stall.  It's an intermittent problem. I tried attaching two mp3 files showing sound when it is working and not working but I guess mp3 attachments are not allowed.