Rebuilt Aquahot problem

[efstewart]

I had my hydro hot system (now called Aqua Hot), rebuilt by John Carrillo of "Heat My Rv", in Colorado, this March, and everything has been going good until this morning. Here in Colorado springs, the overnight temperature dropped to 1 degree above zero a few nights ago, and our heating system kept us warm all night (diesel and electric both working .

This morning I noticed that only the electric system was working ( it is only a secondary heating source). The diesel system stopped working about 5:00 AM. I went to the tank and checked everything, including the manual, and indicator lights on the board. And there were no lights on except for the ones for the electric heating element.

The transfer fluid is full, fuel tank has about 110 gallons in it, and everything looks good.

For some unknown reason the diesel burner is not firing. All of the stuff on the inside has been replaced with new components, and I am plugged into 50 amp service. I left a message for John, he will eventually call back. But in the mean time, I call upon my experts in the field to help solve this dilemma.

[Spdracr39]

There are several things that could be the cause. Fuel filter has water in it, Ignitor bad, burner controller bad, flame sensor bad or dirty, ..... Have you looked at your control board to check for red lights ?

[Smitty77]

Yep, check those items. The easiest being the Control Board light indicators. And also the light on the switch inside the coach when you turn on diesel, is it lighted. How has the 12V supply been to your coach? Any hiccups you are aware of? Would not hurt to push the Reset on the control board (I use a broken in half round tooth pick. It's small enough to slip into hole, strong enough to trigger the reset switch, and wood is safer then metal...).

Just to be sure, is this the 450 series of AH?

Best of luck to you. And please let us know what you determine to be the problem, as it could help others...

Smitty

[efstewart]

In my prior post I mentioned that the lights were blank (control board) except for the ones for electric. No red lights, just green. I have been hooked up to 50 Amp for two weeks, so that is not a problem. All of the "guts", including the fuel filter, ignitor, etc are brand new as of March 2020.

Yes, this is the 450 series. I will try the reset button, even though the electric part of the system s working fine.

[Spk64]

When it quit working did the diesel light inside the coach go out?
If yes this is an indication of a problem with the Webasto Controller. The root cause could be from one or more of several items. Control light in matrix below is the Diesel Burner Light at the switch.

[efstewart]

When I turn on the diesel switch inside the coach it lights up for about 30 seconds and then goes out.

[Spk64]

That indicates a problem with the Webasto. The troubleshooting matrix provides a rough guideline on what might be the problem.

I had the Webasto Controller (box mounted to side of the Webasto Burner) fail on ours which caused same issue.

This is a manual for the burner.
https://www.suremarineservice.com/si...300-repair.pdf

[pointrow]

Do you hear it fire in that 30 seconds? If it does I would clean off the flame sensor. It’s not seeing a flame so it shuts back down.
If it’s not firing I would unhook the control box for a few minutes and try again.
Could be coil, control box, electrodes or a bunch of other things.

Good luck
Pointrow

[Fredward]

Yes they are very reliable until they're not. I had my Webasto 2010 standalone unit refurbished last year 'just in case'. And it worked fine for awhile but then failed. Turns out it was the controller. I bought a refurbished controller and it has worked fine ever since.

Flame sensor could definitely be a culprit if it tries but quits. But I suspect something else in the system. I'd start by verifying everything they did in the "rebuild". They could have gone through it entirely but the controller could fail at any time and they would not have been able to predict that at rebuild time.
Fred

[DJ55]

I'll throw this out there just in case... Did you treat your diesel fuel with winterizer/anti-gel before that super cold night? If not, I wonder if gelling occurred and now your AH fuel filter is clogged. Does your generator run?

[gnvrvin]

Originally Posted by DJ55

I'll throw this out there just in case... Did you treat your diesel fuel with winterizer/anti-gel before that super cold night? If not, I wonder if gelling occurred and now your AH fuel filter is clogged. Does your generator run?

That could be a good call. Would gel up occur if it was running ?
Greg

[Spdracr39]

It should not gel up if it was still running on electric. That should keep the bay warm enough. Mine was doing the same and I replaced the burner controller, no change. Turns out it was the ignitor coil. It would work fine several times then it wouldn't until it decided to work fine again.

[Jean n Steve]

Originally Posted by pointrow

Do you hear it fire in that 30 seconds? If it does I would clean off the flame sensor. It’s not seeing a flame so it shuts back down.
If it’s not firing I would unhook the control box for a few minutes and try again.
Could be coil, control box, electrodes or a bunch of other things.

Good luck
Pointrow

Since he's been at 6,000 feet would the burner be running a bit rich and soot up the sensor?

[efstewart]

I Will find out on Wed what is wrong with this thing. I am taking it to Frederick Colorado ( ABOUT A 90 MINUTE DRIVE) to have John at "heat my Rv", take a look at it

Since he rebuilt the unit in march this year, it is still under warranty.