Aquahot Burner Fail

[oneknight]

Woke up this morning to a cold coach and no aquahot.
Diesel switch on, light in switch off.
No red lights on control board.

Cycled switch, light came on for a while then went off. Blower never started. switch light went off.

Power cycled unit (note it gets power from up front under drivers window compartment. There is a big round yellow handled breaker in there which will kill all DC power to the aquahot) anyway, no change.

Fluid level is fine.

Took cover off, tested interlock switch, it's kinda flaky, jumpered it out, no change, burner blower w/n run.

Getting the manual out now.

[DeWat]

Just thinking out loud, I know there was a batch of bad AquaHot control boards in the Tiffins somewhere around your model year.

[Spk64]

When the Diesel light goes out this is indicating a fault in the Webasto Burner control. This is the silver or black box on the side of the burner\blower motor. The fault could be from any number of issues related to the burner sequence.

[Lv2Roam2]

If you don’t have hot water from the electric side - consider the thermostat. Easy replacement - will need a slotted socket (like spark plug wrench) - believe it’s 7/8th...

[oneknight]

When I turn on the diesel switch, the blower does not come on.

[oneknight]

Troubleshooting done. The motor is the webasto burner has power coming in but doesn't turn.

Aquahot thinks this thing is solid gold and wants $500 for it!

According to the label, it is a Dunkermotoren type GR53X30, a common industrial DC motor available in a dozen different configurations, commonly priced from $75 to $100.

Now to find someone who has just the right variation.

I agree profit is not a dirty word. 100-200% retail markup is fair and reasonable.

500% is robbery

[Gary.Jones]

Jim

Nice job of finding the problem. Please be sure and post what you find as the exact replacement model number for the motor. That model number will go into the trusty "For future reference" computer file.... and hope that I never need it. But, you will be doing a lot of folks a big favor!!

Gary

[oneknight]

I struck out on finding a second source. DW having to use someone else's shower today kinda lent some urgency to the situation.

I got lucky, Lazydays Knoxville, formerly Tennessee RV, had the OEM motor in stock for $540, an hour each way and an hour to put everything back together and we're cooking with gas again.

I did speak with Aquahot this morning, a shoutout to Jim in tech support, he helped me track it down.

Helpful notes:

I had the cover off and the interlock jumpered. If you remove the jumper and put it back on, that will restart the ignition sequence without having to go inside and flip the switch.

There is a clip on the black electronics box on the side of the burner. Release the clip and the box will slide out and come off. Then you can get at the electricral connectors with your meter probes.

C2 and C5 are the wires to the blower motor. 12v there = the board is not the problem, the motor is.

If you have a stubby phillips, you can take the black cover off the burner without taking the entire burner off the unit, and without opening any fuel lines.

The old motor was flat wore out. Both brushes were down to near nothing, and one of the stand holding a brush spring was melted down to the point that the brush was no longer touching the commutator. This is why it stopped working. Motor should have lasted a lot longer than the 3 years it did.

The new motor is SOOOOO much quieter than the old one. I'll no longer prefer heat pumps to aquahot at night due to the noise outside mt bedroom window.

[Rollin101]

Originally Posted by oneknight

I struck out on finding a second source. DW having to use someone else's shower today kinda lent some urgency to the situation.

I got lucky, Lazydays Knoxville, formerly Tennessee RV, had the OEM motor in stock for $540, an hour each way and an hour to put everything back together and we're cooking with gas again.

I did speak with Aquahot this morning, a shoutout to Jim in tech support, he helped me track it down.

Helpful notes:

I had the cover off and the interlock jumpered. If you remove the jumper and put it back on, that will restart the ignition sequence without having to go inside and flip the switch.

There is a clip on the black electronics box on the side of the burner. Release the clip and the box will slide out and come off. Then you can get at the electricral connectors with your meter probes.

C2 and C5 are the wires to the blower motor. 12v there = the board is not the problem, the motor is.

If you have a stubby phillips, you can take the black cover off the burner without taking the entire burner off the unit, and without opening any fuel lines.

The old motor was flat wore out. Both brushes were down to near nothing, and one of the stand holding a brush spring was melted down to the point that the brush was no longer touching the commutator. This is why it stopped working. Motor should have lasted a lot longer than the 3 years it did.

The new motor is SOOOOO much quieter than the old one. I'll no longer prefer heat pumps to aquahot at night due to the noise outside mt bedroom window.

Would this one have worked?

Dunkermotoren GR53X30, 88437 01620, SG62 Servo Motor 24 V 3600 RPM 23 A w/Gearhead T98899

[oneknight]

The motor itself is the same. I didn't try it because of time. It has a 90 degree gear reduction box on it. No idea of shaft length once that gearbox is removed.
It seemed most I found were of that type, geared way down for industrial use. They are very similar to motors in film processors I used to work with.

[Rollin101]

Originally Posted by oneknight

The motor itself is the same. I didn't try it because of time. It has a 90 degree gear reduction box on it. No idea of shaft length once that gearbox is removed.
It seemed most I found were of that type, geared way down for industrial use. They are very similar to motors in film processors I used to work with.

Probably the same if the gear box was removed. Lot of difference between $75 and $540.

[Turbojack]

Rollin101

The motor you have listed is showing 24 volts. I believe the correct one would be a 12 volts motor.