Aqua-Hot Grrrrrr Air Air Air

[Motang]

Well- Still big trouble with the unit. Just had it serviced. Drove it home 1000 miles, expansion tank was empty again. Put in 1.5 gallons of green. Ran great for about 14 hours and-essentially when it gets good and hot, the fluid rises in the expansion tank and out the over flow. Huge air bubbles come out of unit up the tube into the expansion tank. In the last 2-3 weeks we have added over 7 gallons of fluid. There is no fluid anywhere except overflow tank/tube. Have started running individual zones to see if they exhibit different symptoms?

Might have to go to the mothership.

[jestal]

Most of the time the problem with the Aquahot is no heat.

Sounds like you have too much. Possibly a bad control temp thermostat.

Does the diesel burner run continuously? Sounds like it does and never shuts off and is just boiling the fluid out of the system. The diesel burner should run until the boiler is at 185F and then shut off until the temp drops due to demand and then it will turn back on.

Look here and page 22 will start to make sense:

http://www.aquahot.com/files/service...nual_REV_E.pdf

pretty easy fix if it is the control thermostat but you will need a special socket or modify one with a grinder.

This should be a relatively easy trouble shooting job if you follow the manual trouble tree or any competent Aquahot tech or service shop should be able to isolate the issue.

I would worry at this point if the boiler has been damaged by being boiled dry so often. If the burner chamber cracks a leak will be obvious....

[Spdracr39]

Originally Posted by jestal

Most of the time the problem with the Aquahot is no heat.

Sounds like you have too much. Possibly a bad control temp thermostat.

Does the diesel burner run continuously? Sounds like it does and never shuts off and is just boiling the fluid out of the system. The diesel burner should run until the boiler is at 185F and then shut off until the temp drops due to demand and then it will turn back on.

Look here and page 22 will start to make sense:

http://www.aquahot.com/files/service...nual_REV_E.pdf

pretty easy fix if it is the control thermostat but you will need a special socket or modify one with a grinder.

I think the special socket is the same as an o2 sensor according to a you tube video I saw. Slotted on the side for the wires.

[Kiss4aFrog]

In the instructions it's calling for a 7/8" socket and that would be a common O2 size. If that sensor is bad you can usually get one of those sockets from an auto parts store as a loaner.

[Motang]

Thermostat control sensor was replaced Friday.

Yes the fluid is very hot, not sure if it is actually "boiling" out. Seems to me that air is building in the system and forcing the fluid back out the overflow. It takes time, several hours, before it happens. Seems to come up to temp before expanding to overflow capacity. Then you can watch the air bubbles come up the tube from unit into the overflow tank and force fluid out the overflow tube from the expansion tank.

[RTC1]

You should check out Roger Berke forum. Very informative

[Cruzer]

It could be a bad check valve. If they stick in the open position the fluid in the floor heating zone can drain down with gravity, causing the reservoir to flow out the overflow tube. I had that happen once. Everything was fine when running but after shutting it off it would drain down. Once I fired the system up it pushed the air out and the fluid level in the reservoir went down and needed refilling. A small rap with a hammer on the check valve corrected the sticking.

Usually they freeze in the closed position, which results in no heat to that zone but I found they can stick in the open position too.

[Gary.Jones]

Here is the link to Roger's webpage. You need to register with his site to get full access to his file of previous questions and answers. Roger is a very skilled AH tech. You can ask him questions and he will point you in useful directions.

It sounds like you have gotten a couple of good recommendations here on what to try. What you are experiencing is definitely not "normal" and the problem is probably pretty simple if you get someone with the right knowledge about interpreting problems from symptoms.

Hang in

RV Hydronic Heater Repair - Home


Gary

[Motang]

Thanks Gary
I registered

[Gary.Jones]

You making any progress with your AH Pat?

Gary

[Motang]

Hey Gary thanks for checking in.
Unfortunately yes and no. I started to stress test the zones individually. When running zone 3 the reservoir would fill and back up out the overflow tube. Ran zone 1 next and the opposite happened, the reservoir was empty. Wanting to keep the fluid proper I yet again added about another gallon of fluid. Then my breakthrough of sorts, after adding fluid time after time it had to be going somewhere? I crawled through top and bottom of that coach on the hunt. I removed the carpeted panel in the far back passenger basement compartment and noticed antifreeze pooling in the bottom.
At first I thought there was a leaking hose in that compartment, but then discovered it was coming from a hole in the ceiling of the compartment. Sooo I now know I have a leak under the floor. I assume it just took a lot of fluid to get to a point that it started to show itself.
I am off to the Mothership next week ( Thanks Joyce ).

[Gary.Jones]

Pat

So sorry to get that news.... that is not good news. However, Entegra and Joyce and her people will do what needs to be done to get the problem resolved. That is the reason that most of us bought Entegra..... they will do you right on the repair. They took out much of my front inside cabinetry and sheet rock to resolve a leak I had.... I developed great respect for their willingness to make repairs that clearly derive from their construction problems.

I assume that they will get it completely resolved and your coach back in good order. Is there a guess on what is going on? Leak in PEX running through floor? Leak in a joint somewhere? Or cause and problem TBD?

Gary