Atwood GC10A-4E water heater

[Paul R. Haller]

I have a 2005 Fleetwood Triumph 5th wheel model 365BSQS king bed, quad slide, 2 fireplace trailer. In recent years I’ve put on a new roof, a new in January Samsung RF18 fridge, and more recently a Fisher and Peykal drawer dishwaher. It has all its original Atwood propane furnace and a 120 volt propane combo water heater model gc10a-4e. Many years ago the propane side stopped working completely but the electric worked fine. I almost never boondock with this behemoth so I just kept using it on 110 volts ac. On a trip to Portland Oregon from the SF Bay Area we encountered some snow up hiway 5 near mt Lassen and we rerouted over to hiway 101 near the coast to get around the snowy conditions on 5. That worked fine and we pulled in a campground. I hooked up as usual and turned on the hot water to 110ac about 3 in the afternoon expecting to shower later after dinner. No hot water was to be had. I got up the next morning and drove the rest of the way to Portland where we were to stay a week and began checking out the water problems. I ended up reading all the stuff on that Atwood heater I could find on the web and now armed with some info and a VOlt Ohm meter began troubleshooting the water heater.

I tried getting to the rear of the unit to check the 12 volt dc relay that directs power to the 110 element, but that was nearly impossible. I decided to undo the water lines and slide the heater out about 3 inches so I could access the rear. There is a plastic cover on the rear that houses the connections to the electric heater as well as the relay that turns on the 110 ac to power to the heating element. I figured if I hot wire the relay to energize the relay that both the relay worked and that when on actually transferred the 110 ac to the heater. They both worked perfectly. I slid the heater back in place and began trouble shooting the why it was not functioning when all together. It appears that a t stat on the heater itself is supposed to be a normally closed switch and opens when temperature of 140 degrees is reached. Turning the relay off but my t stat was open. There is also a flame detector that is in line through the power lead to the t stat to disable the heater if flame is detected outside the flame area. It was fine and flowed current. I already knew the propane didn’t work at all and figured based on that that I needed a new circuit board, to fix the propane and a new tank t stat both of which were available on Amazon. The tank t stat and an overheat safety come as a set for 10 dollars and the circuit board from Atwood was about 100 dollars. A new 110 heating element was about 20$.

More reading revealed that Atwood circuit boards are of notoriously poor quality and many people reccomend buying only dinosour circuit boards that are very good quality, carry a 3 year warranty, are made in the USA, and are only about 25 $ more then the Atwood made in China board that carry a 6 month warranty. I bought the heating element for 20$, even though mine was fine, a dinosour UAB-59 circuit board, and tank mounted t stat, and tank mounted preventer that sit side by side on the outside under the exterior cover as a kit for 10$. I also ordered 1roll of grey butal tape and 50 new self tapping stainless screws. I am a prime member that gets free and guaranteed 2 day shipping. The entire order was just over 170.00$ and arrived 2 days later at the trailer park.

I picked up my order and checked to be sure all was there and reinstalled the hot water heater with new butal tape and new screws, put in the new t stat and preventer and finally, the new circuit board. To my surprise the new dinosour board came equipped with led lights on the board to show calling for gas, calling for 110ac, and gas not lighting, along with a weather resistant plastic cover to prevent damage to the new circuit board.

Moment of truth.... I hooked up water, filled the RV water system, check for any water leaks, and with a deep breath walked inside the trailer and hit the heat by propane button. On came the light briefly and then the familiar wooosh of ignited propane. I walked outside to check and all was working as it should. That was the first time propane was used to heat water in my trailer for probably 13 years! I turned off the propane and turned on the electric element. The light on the board lit with calling for 110ac. I went inside and cleaned up and after making lunch checked for hot water by turning on the kitchen faucet. Success! 140 degree hot water. All works as it should. I should also mention that before buying the parts I also checked that the switch wiring all worked properly, that the switches both delivered power to the heater, and pulled off the gas burner and adjusted and cleaned the igniter and checked the solonoids on the gas valves to be certain they are were functional. I’m a happy camper again.

Don’t be afraid to fix problems with anything on your home away from home. Armed with some tools, a lot of reading on here and elsewhere about the wiring and the sequence of the water heater firing on gas and heating by 110 ac, you too can be a happy camper. Before trying this I called an RV repair center in Portland with a possible repair quote. They simply said 100$ an hour plus parts. Minimum diagnostic fee of 200$ That would be applied to the repair. I asked them about an Atwood circuit board and they quoted me 175$ for the 89$ board and they did not even carry or would get me the better built and longer warranty dinosour brand board plus 1 hour to replace the board. To replace the t stat and preventer a further .5 hours. I figure I saved at least 400$ by doing it myself. I also learned a lot of how Atwood heater really work, their lousy board reputation, and how to fix them for the future Atwood catastrophe.
-Paul R. Haller-

[Old-Biscuit]

Glad you got it working


Seeing as DC is used to control both electric and propane functions on your Atwood the 1st thing you should have done was trace the DC Circuit and find where it wasn't when it should have been


*Thermal Fuse.....when it blows (190*F) it shuts down ALL DC from circuit board (Brown wire) that means NO Propane but also NO ELECTRIC
*T-stat....when they fail typically end up with overheating on electric & propane
(Open/140*F---Closes/110*F)

*ECO (Energy Cut Off---HI Temp t-stat) uses 12V DC when on propane and 'Millivolts' DC when on Electric so it is part of control loop) Opens/180*F.....Closes/150*F and will trigger the RED Fault Light when it opens
*DC/AC Relay....YELLOW Wire...has to have 12V DC when on electric so 120V AC can go to element



Dirty contacts/Loose connections etc will stop DC
Atwood circuit boards of your vintage are typically GOOD boards
Atwood did have a slew of faulty boards when they changed suppliers....new boards/replacement boards from Atwood, Dealers, Vendors etc were bad.
Atwood resolved that issue and as of Sept 2018 ALL Atwood boards were not an issue


Dino does make a good board. And is a frequently used option for Norcold/Dometic boards when a replacement is needed


Follow the DC


Atwood Electric/Propane wiring for GC6A-10E and GC10A-4E (since 2004)

[Paul R. Haller]

Old Biscuit, I did check the traces on the old board as per the instructions from Atwood and they were open on both the electric and propane traces. The thermal fuse tested good with continuity so not replaced. The t stat tested partially open with 2000 ohms resistance so, it was bad also. I did not bother testing the eco because the eco and t stat come bundled together for 10$ and would be replaced as part of the set. I worry always about grounds too so, I added a wire ground from the case of the water heater to both the igniter through screws and the solonid gas valve and cleaned and regaped the igniter. I also cleaned every ground point I could find including the ground connections on the back of the tank from 110ac and the other ground from the relay. After installing both the tstat and eco they both tested 0 ohms resistance across them both. I also cleaned the connections on the board, eco, t stat, and thermal fuse, before doing anything else as I agree that poor connections are the most probable cause of 12 volt dc failure. I also tested resistance with circuit board removed to ground at 3 ohms resistance. After cleaning all grounds that resistance dropped to 0.

[fotis]

I have the same problem you did my Atwood water heater it's not working on the gas it works 3 years ago when I buy the trailer for few months and then it shuts off my circuit board light it was working erratically and then it stops working all together. I go to an RV place in my area and they told me that circuit board its malfunction it and need to be replace . I like to replace it but not with Atwood I prefer dinosaur circuit board. I look on Amazon but I could find dinosaur circuit board replacement for Atwood(atwood model GC6AA-10E with circuit board number 93851) any help would be appreciated Thanks

[Old-Biscuit]

Originally Posted by fotis

I have the same problem you did my Atwood water heater it's not working on the gas it works 3 years ago when I buy the trailer for few months and then it shuts off my circuit board light it was working erratically and then it stops working all together. I go to an RV place in my area and they told me that circuit board its malfunction it and need to be replace . I like to replace it but not with Atwood I prefer dinosaur circuit board. I look on Amazon but I could find dinosaur circuit board replacement for Atwood(atwood model GC6AA-10E with circuit board number 93851) any help would be appreciated Thanks

Dino UIB64 would be the correct replacement circuit board for the 93841
UIB 64 page

[fotis]

Originally Posted by Old-Biscuit

Dino UIB64 would be the correct replacement circuit board for the 93841
UIB 64 page

Mine is 93851

[Old-Biscuit]

Originally Posted by fotis

Mine is 93851

TYPO.....


Did you even open the link??

[fotis]

Originally Posted by Old-Biscuit

TYPO.....


Did you even open the link??

Yes I did (the recommended a qualified technician to do the job due to the dangerous of the propane gas)

[Paul R. Haller]

Fotis, just turn off the propane 1/2 hour before replacing the board. It will be fine. I suggest you check both the eco and t stat circuit as well as your electric heater circuit before proceeding to be certain you do not have open circuit on either. If either circuit is open a new board won’t fix your problem. I didn’t check your heater specifically so call dinosaur to confirm the correct board.

[Old-Biscuit]

Not unhooking any propane lines/connection to replace a circuit board.


Just unplug the connectors....remove mounting screws


Install new board












Oh ----never mind

[fotis]

Originally Posted by Paul R. Haller

Fotis, just turn off the propane 1/2 hour before replacing the board. It will be fine. I suggest you check both the eco and t stat circuit as well as your electric heater circuit before proceeding to be certain you do not have open circuit on either. If either circuit is open a new board won’t fix your problem. I didn’t check your heater specifically so call dinosaur to confirm the correct board.

The only open circuit i found is between ground(green wire) and lamp( blue wire)according to the manual this is caused by a short in the blue wire between the unit and the switch.wiring must be corrected before circuit board is replaced.Bottom line is I'm going to use the water heater on electric(is working fine on electric) .lm going to rv parks with full hook up anyway till that one died to then I go to the local rv to fix it.( that might take weeks months or years like yours who knows time will tell) anyway thank you guys for the help.

[fotis]

Originally Posted by Old-Biscuit

Not unhooking any propane lines/connection to replace a circuit board.


Just unplug the connectors....remove mounting screws


Install new board












Oh ----never mind

Well finally break down and I by the dinosaur board I install it and it works like a charmAttachment 1