Hydro-Hot Reservoir

[Joel & Mary]

We just spent a week at WRV. In that time, the reservoir went from the full-line to the low line, and that was only using it for short periods early morning and evening.

WRV could not find a leak. However, the anti-freeze/water mix is going "somewhere". We had filled it to the full upon our arrival there. They watched it go down, but did nothing to correct.

Anyone got some ideas?

[Joel & Mary]

We just spent a week at WRV. In that time, the reservoir went from the full-line to the low line, and that was only using it for short periods early morning and evening.

WRV could not find a leak. However, the anti-freeze/water mix is going "somewhere". We had filled it to the full upon our arrival there. They watched it go down, but did nothing to correct.

Anyone got some ideas?

[dgerstel]

Joel & Mary,

My tank only has a cold and hot level lines on the tank (reservoir). If the tank was filled to the top (hot) level when it was cold, then when the system heated up the tank would probably overflow. It would only take a single use to do this. Does it ever go below the low (cold) line?

Dale

[Joel & Mary]

Reservoir was filled when hot while at WRV. Went down to low line....This has happened twice..once going down below low line and going inoperative. We are often needing to add liquid.

We live in Orange County, CA. Meant to say that in original post. We need good service technician. Was shocked that WRV wasn't able to help.

[takepride]

I'd recommend Coach Care in Irvine (405 @ 55). They specialize in Cummins engines and have adeptly repaired or upgraded several components on my coach. Ask for Shawn (service writer) and Michael (technician). They are a part of CalPacific Cummins and ought to be able to handle it easily. They are authorized to do WRV warranty work.

I saw a new Alpine in there when I dropped mine off the other day for an awning repair. Mechanic reported it mostly had piddly repairs but was waiting on parts.

[dgerstel]

The most likely places for leaks would be at the AquaHot unit it self or at any connections. The water is run thru plastic tubes with flexible connectors at the ends that are held in place with spring clamps. I would look with a mirror and flash light at these places:
All around the AquaHot unit itself.
At each heat exchanger, dash, under couch, under drawers to left of sink, bathroom, bedroom and behind water tank in the basement.
I haven't looked to see where, but at the engine.

Dale

[APEXMAN]

If you are looseing a couple ounces a day it might be in the carpet under the bed or couch or dash.Good luck!

[Wayne R]

Joel and Mary

The Hydro Hot unit is notorious for developing a leak at the plastic drain valve. If you remove the front cover you should be able to see liquid pooling if that is what is leaking. I also had a leak at one of the stir pumps (cracked hose barb).

[EngineerMike]

J&M- Google Hydro Hot to find them online. You can download their pdf file for service & troubleshooting. It is pretty comprehensive. Any service tech fooling w/the unit should have this in hand.

I suspect you have a leak that hasn't been located. The coolant level should be pretty stable even w/regular use. Could be a fairly esoteric leak, like @ the internal heating tank of the HHot unit itself where coolant has a chance to evaporate, but that's the last place I'd look after checking all the connections. One other possibility is that it was never filled fully, and it is continuing to push air outa the system (also less likely than a simple leak).

If you are doing some DIY probing around, call HHot @ 800-685-4298. They have excellent tech support. On my 06 unit they sent replacement electronic component (I had to pay by credit card & they refunded when I sent them the burned up part) on my diagnosis, and were very helpful over the phone.

[Wingding]

Engineer Mike,
Did you say "burned up part" ...? Because thats very interesting...because that is exactly what I had... a burned up part/s.......... although I got no refund for mine... :+0 !!

seems things either melted or burned...take your pick... I just find that very interesting...I got a strange feeling this probably the same thing that happen to mine.

Were you ever able to come to a conclusion as to what was the cause of your Hydro - Hot malfunction????????

[EngineerMike]

Wing- My problem was easy to diagnose from the HHot service manual off their website. I opened the 4x4 metal electrical box where the WRV romex enters the system, shut off the power before inserting my fingers, and checked anything w/burned insulation. One of the gizmo's was a "limit switch," or thermal disconnect device that shut off power when tank reached a certain level, and that was what the manual said to check; it had a lead burned through. The lead end had grounded out against a WRV-installed neutral wire or else the bare Cu ground off the romex circuit feed. I sent WRV a diagram showing how to wire the feed circuit leaving the bare ground wire outsied the box, and eliminating other wire congestion inside. The basic trouble was shoving excess wire into an already crowded box. You can read more about it here

Your problem sounds like it was outside and or under the unit.

[Wingding]

Actually Mike,{This will take some explaining}
originally my "limit switch" melted...Same as you!
The smell when I entired the coach was the clue... when I took the hydro hot cover off, eventully I found it. I believe it was a black threaded plastic with wire leads. Now as a result of this, at the same time the plastic anti freeze drain literally came off in my hand.It had melted the threads area. There was also a piece of tubing behind the hydro hot that melted through...
Now after all this anti freeze dispensed underneath the hydro hot box - eventually it had some kind of affect {from my observations} with the aluminum plating and all the extra coils of grey sheathed cable.From there the sheathing melted together wires within.
Funny thing was this was all discovered long after the original limit switch melt down.Months latter....
Im going over it with a ohm meter and Don from The Hydro Hot company is saying MARK YOU GOT A SHORT on that pair- follow it out- so I am following this grey cable right under the hydro hot- needless to say after following it inch by inch down the line, there it is, laying there all coiled up stuffed under the hydro-hot. It was not much of a area that was affected but it had melted through or Burned the cable and found its way to a couple wires which were definitely shorted together.The anti freeze had pooled in that particular area.
Faulty limit switch allowed things to get to hot- melting the cheap plastic and dispensing anti freeze over cables that, in time, developed a short.
At least thats how I think it went down and why I think we had the same problem. It's just you did not know,as Andy Rooney says..The Rest Of The Story.
When I read that thread... You said "Burned up" it kinda brought back the memory of those melted/burned parts...only it appears that you did not have as much damage as me.{Maybe having the electric 110v on at the time also contributed to extra damage,I do not know....But Thank You, I have a better understanding of what took place now.... I guess the overall final analysis.... Them LIMIT SWITCHES are extremely faulty !!!

[EngineerMike]

When they shipped the replacement limit switch, I bought a second just-in-case one. Never needed it (so far).