Atwood 10 gallon LP/electric will not heat

[HD4Mark]

We have an Atwood GCH10A-4E ten gallon LP/ electric water heater that will not light or run on electric. The LP tank is full, ECO, thermostat and igniter all new. I can hear the gas valve click open, the igniter clicking and if I use a small torch I can get it to light while the valve is open but it shuts right down in about 5 seconds and I get the pilot out red light on the panel.

The inline thermal fuse also tests good. Any ideas what to try next. Thank You.

[BFlinn181]

First, make sure the tank is full of water. Empty, the high temp thermister will shut it down very quickly. This manual covers your WH, there are also other troubleshooting guides online.

You could also remove, spray contact cleaner on, and reinstall all connections to the control board. It sounds like a bad control board on first guess. If you take the board to an Atwood service shop they can test the board.

[HD4Mark]

Originally Posted by BFlinn181

First, make sure the tank is full of water. Empty, the high temp thermister will shut it down very quickly. This manual covers your WH, there are also other troubleshooting guides online.

You could also remove, spray contact cleaner on, and reinstall all connections to the control board. It sounds like a bad control board on first guess. If you take the board to an Atwood service shop they can test the board.

Thanks Bob. Good info. I did not know about the tank being full. It should be but I will hook up a garden hose and make sure. I will also try contact cleaner. There is a RV dealer nearby that Dometic lists as a repair shop so if all else fails I will take the board there.

[rk911]

is the thermal cutoff diode blown? check for continuity.

[BFlinn181]

Originally Posted by HD4Mark

Thanks Bob. Good info. I did not know about the tank being full. It should be but I will hook up a garden hose and make sure. I will also try contact cleaner. There is a RV dealer nearby that Dometic lists as a repair shop so if all else fails I will take the board there.

With your water pump on or connected to city water, if you take the outside cover off the WH, the pressure relief valve should be at the top of the tank. If the water heater isn't working, go ahead and flip the lever for the valve. Water should come out if the tank is connected to your water system. Let the lever snap closed, it helps dislodge any deposits that might make the valve weep.

[phays]

On the electric side, the thermostat and ECO are on the back side of the water heater. The ECO works something like a circuit breaker and will need to be reset if tripped. There is a small button to be pushed to reset the ECO.

If exercising the connectors does not solve your problem you need to test the control board. Find an Atwood service manual online to see how to trouble shoot the water heater.

[Old-Biscuit]

1st off...
If thermal fuse was blown you would have to bypass it or replace it cause they are a one-shot device that blows at 190*F and shutdown ALL DC functions
2nd...
Your model being 2004 is first year that Atwood incorporated ALL functions being controlled by circuit board.electric and propane. 12V DC is used to trigger the 120V AC to element and for propane gas valve/spark electrode.
Electric & propane use same set of t-stats ----the t-stat/ECO in outside compartment
3rd...
Gas valve clicking....spark electrode firing but doesn't light main flame
YOU can light main flame via small torch but flame goes out

What does flame look like when YOU light it? Strong BLUE flame or weak flame with yellow tinges?

Is the spark electrode engulfed in that flame when it lights??
Has to be in order to return flame signal
Is spark electrode GAP at 1/8" (3/16" MAX) so spark is STRONG?
Is flame spreader parallel with end of burner tube so flame is evenly disbursed?
Spark electrode high voltage wire....clean/tight connection!!
When flame lights off a 'flame proving' signal is generated that goes back to circuit board via spark electrode so circuit board will hold DC on gas valve, No return signal/no dc on gas valve.......FAULT Light triggered
*DC Voltage is only on gas valve solenoids for 6-8 seconds during ignition

[HD4Mark]

Yesterday between raindrops I made sure the tank was full. The MH had been sitting. Pulled the relief valve a few time with a bucket under it to make sure. Went inside, turned on the switch and could hear it light. Great! A few minutes later I checked on it and it was out but not heated enough.

Now I can still hear/smell the LP and can ignite it with a torch but it still goes right out. I cannot hear the (new) igniter click now though and could before. Turning on the 110 switch doesn't seem to do anything.

I did clean up and check the contacts on the circuit board. I have it out now and found some simple continuity tests online I will try with my VOM before taking it to an Atwood dealer. Pouring rain again and I need to write down what color leads go to which pins to test when it quits.

[No Sweat]

always take a photo with your phone before removing any wires !!!

[HD4Mark]

Originally Posted by No Sweat

always take a photo with your phone before removing any wires !!!

No problem putting them back on as one is 4 pin the other 6. I will be taking a photo just to get the colors. There are only 3 possible connections so I will say they made that part easy.

[HD4Mark]

UPDATE: From this link Atwood Water Heater Troubleshooting
I see how to test continuity on the potted circuit. Power track green (ground) to top power wire, brown. Lamp track green to the blue and valve track green to red. All three are open. Seems unlikely so I buffed up the contacts and same results. I only see continuity between the 2 greens (duh) and green with orange and white that if I'm reading the schematic right are connected to the remote switch inside.

I'll keep you posted.

[Old-Biscuit]

You didn't answer any of my questions about flame/spark



Yes,,,
White and Orange are connected to the 2 on/off switches

White is for Electric
Orange is for Propane


Common 12V DC (fused) goes to those 2 switches
Turn one on and DC goes to circuit board

Then DC.......thermal fuse/t-stat---lower connection to circuit board upper connection (BROWN)
DC then ECO/Gas Valve...full 12V DC when on propane/millivolt when on electric (RED)
On electric DC to relay for 120V AC (YELLOW)---DC Relay inside cover over element (backside of WH Tank)







No Continuity-------Bad board
Get a Dinosaur Electronics for replacement with protective cover


(But no continuity---NO DC to gas valve/spark electrode so no ability to light flame....no gas valve click etc)

[HD4Mark]

Originally Posted by Old-Biscuit

You didn't answer any of my questions about flame/spark

No Continuity-------Bad board
Get a Dinosaur Electronics for replacement with protective cover


(But no continuity---NO DC to gas valve/spark electrode so no ability to light flame....no gas valve click etc)

I did have spark until yesterday, then none.
Dino board is my plan.
I stopped at a local RV dealer who would be happy to charge me to test the board. Also happy to sell me a new one for $170 and the only one he had was with pin connectors and had no adapter.

Thanks for all of the help. I do appreciate it.

[HD4Mark]

I called Dinosaur electronics yesterday to ask about how to test the board and the guy that answered was very nice, and actually answered the phone. He said I really need to connect it back up and measure voltage, not continuity. It was pouring rain all day so he said just call us back and we can walk you through it.

Since they are west coast an I am east I decided to get everything set up this morning and see what I can see before calling. I tested the leads I thought he mentioned and thought they looked like they were powered OK. Could still not hear the igniter. So I reset it stuck my meter probe in and not only could see voltage but hear the spark. Any time I let the pressure off the connection, the igniter went off. It looks like there is a small crack in the round part that the igniter connection comes out of so I'm guessing a new board is the fix.