Hot water coming out of cold water side

cooper31525

Hello everyone.  I have a 2016 T@B CS-S Max (clamshell) with the Alde system and I’m having a plumbing issue.  For some reason I am getting intermittent hot water coming out of the faucet when I have the cold water turned on.  The cold runs for a second or two and then hot will run for a second or two.  The only thing that I’ve done that may have caused this is winterizing but I feel like I winterized correctly, based off a manual I found online.  Can you think of anything else that could cause this?  Bad mixing valve?  Thanks.

ScottG

Any chance you left the Alde bypass open when you dewinterized?

cooper31525

Thanks Scott.  Having a valve in the wrong position was my first thought too but I have gone through this manual a few times with no luck.  https://us.v-cdn.net/5021717/uploads/editor/lm/17m30l0a7xvi.pdf  Maybe I should check again.  I may be missing something in the directions.

ScottG

The Alde bypass valve is labelled in the first photo in your link. It should be turned so it is perpendicular to the pipe (the specific direction doesn't matter, however). Forgive me if I'm stating the obvious.

If the bypass valve checks out, than I would turn my suspicions to the mixing valve.  

cooper31525

Thanks again.  I will double-check the valves and if that doesn’t work, I’ll try the mixing valve. I’m guessing the mixing valve would be a replace instead of repair, right?  I guess the only “repair” would be if an object has somehow worked its way into the valve and then I could remove it.

ScottG

I think it would be a replacement, but I'm not certain. Mine is a 2015, built before the mixing valves were incorporated.

Good luck and please let us know what you find.

cooper31525

Will do.

JohnDanielsCPA

I need to better understand this - the mixing valve determines how hot the water will be by mixing hot and cold water together, then sending that water down the hot water line to your sink.  It should not be impacting the cold water line at all.  So if you have the cold water on but are getting intermittent hot water, that does not make sense to me understanding how the plumbing works.  Is it possible that you do not have the cold on all the way at the faucet, so you are getting hot mixed in with the cold at the faucet somehow? Then, if you are getting intermittent hot/cold (from the hot water supply pipe), a bad mixing valve would make sense.

cooper31525

Hello and thanks for your thoughts.  I get intermittent hot and cold water in both sinks and the toilet. 

rustyshibley

This forum is super helpful for us--especially the Winterizing Link with the diagram.  We are new owners of a 2016 TAB CS-S and heated water for the first time and discovered scalding hot water coming out when turn on either the hot or the cold faucets in either sink.  We are trying to determine if one of the valves is turned wrong or if we have a defective mixing valve.  Kind of hate towing it to an RV repair shop.  Most likely they won't have any better idea what the problem is than we do.  Please let us know if you did replace your mixing valve and if that fixed your issue.  Thanks!

RollingBnB

Do you have the outside shower? Make sure those valves are turned off or the hot and cold will mix in the shower control head.
Never mind, just saw how old this is.

Sharon_is_SAM

@rustyshibley, check the Alde bypass valve.  I am looking at the camping season settings in the Tab manual, and that valve should be turned off.  If left open (parallel to the pipe), it appears that the hot water would mix with the cold water beyond the mixing valve.  Let us know what you find.  I will try to attach a plumbing diagram.

Sharon_is_SAM

Sharon_is_SAM

Curious if hot water is coming from the toilet flush.

MuttonChops

SAM said:

Curious if hot water is coming from the toilet flush.

Not having both winter by-pass valves in the correct position can cause this to happen.

Did happen during my new T@B walk through.  The young 'delivery prep' guy had to track down the service manager and in a few minutes he had things cleared up.

Cold would flow, then hot (until 2-gallons tank was empty), then cold.

And it was real hot . . . would not have been enjoyable to be sitting on the toilet . . .

Sharon_is_SAM

@MuttonChops, which other valve?

MuttonChops

MuttonChops said:

Not having both winter by-pass valves  . . . .

Sorry, my error. The one by-pass valve.  Service guy was also playing with the HW & CW disconnect valves to the Alde . . . . but think he was just trying  everything to get a customer out of the shop.

welovenaples

PLEASE HELP! I just bought a used 2016 T@B 320 and just about ready to send it to it's grave over hot water issues.  I too am experiencing hot water coming from the cold faucet(s) then after 30 seconds turning cold - no problem, I guess.  But the hot side never gets hot.  The forum has been great about the valve positions.  I am confident I have the valves correctly set to "camping" mode i.e., bypass closed, hot open, cold open, drains closed.  The mixing valve has me quite confused.  Pic attached for verification.  Twisting it the opposite of my pic will shut off hot side completely.

ScottG

@welovenaples, I don't have the mixing valve so I can't help much. I do recall that others have had problems getting it adjusted properly, possibly even to the point of replacing it.

If you haven't already done so, search around here and I think you will find several other threads that might offer some clues.

falcon1970

@Sharon_is_SAM I apologize hijacking this thread, but do you also have plumbing schematics for the TAB400?  And while we are at it, schematics for the other systems--Alde cabin heating, electrical, and air conditioning?

Sharon_is_SAM

@falcon1970

This is the only one I can find.  We need some creative 400 owners to step up here😊

https://tab-rv.vanillacommunity.com/discussion/7334/tab-400-wiring-and-plumbing-diagrams

@ScottG, can you add this to the User Manual/PDF thread, please.  

Sharon_is_SAM

@welovenaples, please check out this thread.  If you are confident you are turning the valve correctly and still have limited hot water, then order a new mixer valve as that is most likely the problem.  

https://tab-rv.vanillacommunity.com/discussion/comment/36103#Comment_36103

welovenaples

Can anyone refer a source for acquiring a new mixer valve?

jgram2

Call Elsie in parts at NüCamp 844.823.9112 x 304. NüCamp numbers and contacts are n the category column on the left hand column.