Atwood Water Heater Assistance

[RRR]

Atwood GC10A-4E

Had a fire sometime ago, don't know when till I was prepping for trip. The thermal fuse didn't melt but the rest wiring melted and toasted, and the cover for the board melted. Board and ECO is okay (confirmed by test fire).

Picked up the wiring harness, got it installed, cleaned burner tube and the heat tube, took off the orifice and soaked and blew out, tested the stove burners and had nice blue flame. Test fired. Repaired some of Fleetwood's other fine quality workmanship.

Fired today, but it felt that more heat was escaping from heat (2" ) tube at the bottom where the burner enters, but I really don't know as it isn't like I run it with the door open. Flame while blue seemed lazy, not the typical roar of the WH. Closed the door and went to turn off. Came back to the WH and had a lazy, smokey fire. Wiring and board cover again toasted.

Any ideas? Air fuel ratio off? Air shutters are about 7/8 the way open Regulator going bad?

Thanks

[Old-Biscuit]

combustion/exhaust 'U' tube maybe obstructed....remove exhaust shield/remove burner tube/spark electrode
Run a wire thru 'U' , tie a rag to it and pull back thru 'U' tube (chimney sweep.

Burner tube....check that it is clear and spreader plate is parallel to end of tube
Air shutter sleeve should be 1/4 open (standard OEM position)
Burner tube needs to be 'aligned' so gas flow down center of tube for proper air/fuel mixture
*if gas is bouncing off side of burner tube it will not mix with air correctly


Low LP Pressure...
Hard to visually tell pressure is correct thru out system as it is only 0.39 psi (11"WC)
Stove has it's own reg under stove top that is set for 10"WC (0.36 psi) so stove burners are NOT good visual

Lazy/smokey flame..........typical fuel rich condition


Manometer is used to measure system pressure
New Regulator is cheap and easy (2016 reg is 8-9 yrs old)

Notice position/opening of air shutter

[RRR]

Thanks O-B

Ran the shop vac hose up the combustion tube about 14-16 inches. Will do the rag idea to be certain.

Burner tube clear and spreader plate is dead center and square to tube and tube is centered to combustion tube. The air shutter was at about 7/8 open so that is where I set it back to. Peeked at the neighbors Atwood and his was at 3/4 open. I'll start at the 1/4 and see how it goes.

Already got the regulator in the shopping cart, hope my control board is still good after barbecuing it twice.

So to be clear too much air would still give a blue flame? Just sorta lazy?

[veraken]

Here is the Atwood Service Manual which may help

[RRR]

Been off/on with this with no cure. Runs fine on electric so I go hot water but one of these days might need the gas.

Have run a rag from end to end thru the combustion tube three times. Burner tube clear, spreader centered, shutter at 1/4 open, replaced propane regulator. Nothing has changed.

On light up I get brief orange flame that quickly changes to blue. But doesn't draw up the stack, it sort of blows back and floats up the front of the water heater.

Where to now?

[VolDawg]

Something to check per Atwood service manual...

[RRR]

Originally Posted by VolDawg

Something to check per Atwood service manual...

It is dead center in the tube, spreader set correctly and shutters at 1/4 open.

[azpete]

check the lp water column pressure in and out of the main valve. it sounds like either a bad valve, or partially blocked orafice. either will cause a lazy flame.

[RRR]

Originally Posted by azpete

check the lp water column pressure in and out of the main valve. it sounds like either a bad valve, or partially blocked orafice. either will cause a lazy flame.

I started again from square one yesterday. The orifice seemed to have a little of something in it. Soaked it for several hours and blew it out. Hope to get back on it later but got to help Wife with some things.

I figure that if cleaning the orifice didn't work I'll try to find a manometer, any suggestions for one that doesn't total the bank account? I never thought about the gas valve, how would one check that? The regulator was replaced but I suppose it could be faulty.

[PS89]

You can make your own manometer with some clear vinyl hose, a ruler, and some water.

[RRR]

Jury-rigged a manometer and checked the replaced propane regulator and the gas valve, both showed about 12.5 WC. I know that it should be 11 WC but figured I might be a little off. Tested the old regulator and it showed the same. Replaced the orifice with no change.

To sum it up I have:
1) Ran a rag down the combustion chamber three times, and blown out and vacuumed. Also ran a borescope to see if anything the cleaning missed.
2) Changed the propane regulator, checked the gas valve and new regulator with a manometer both showing 12.5 WC. Put the old regulator back on and it read the same
3)Confirmed that the air intake is set correctly, (Also played around with the intake from 1/4 way open to 7/8 open, which is where it was originally set at.)
4) Flame spreader is centered on tube
5) Tube in combustion chamber,
6) Soaked and blew out orifice
7) Replaced orifice.

Ideas?

[egwilly]

I got a manometer with a case for around $35 on Amazon.

Worth it's weight in gold when troubleshooting gas lines and such.

I'm thinking you have low gas pressure/volume. This will tell you.