Discovery: Water heater

[flesslie]

I have a 2005 Fleetwood Discovery. The water heater is not working on gas or electric. I've checked all fuses & circuit breakers that I can find. I'm not sure what to check next, anyone have any thoughts? Thanks

[flesslie]

Forgot to mention its an Atwood water heater.

[Skip426]

Have you had the outside cover off , and checked for wiring damage , Atwood has had some issues with burner flame getting to the wiring and melting it .

Also a small fuse on the control board that needs to be tested .
Do you have the manual , the trouble shooting guide in the manual is usually pretty good .
They are available as a free download , if you don't have one .

[Old-Biscuit]

2005 Atwood gas/electric uses 12VDC for control....same set of t-stat/ECO, same circuit board etc
*GC10A-4E---10 gal OR GC6A-10E---6 gal

Same 'Thermal Fuse'....in the clear tubing connected between circuit board and T-stat (brown wire)
Blows at 190*F when exposed to flame from blowback
If blown...NO DC to circuit board so neither gas/electric would work

Unplug it from t-stat and Brown wire.....connect Brown wire to T-stat
then try Electric
*try gas but be aware that the thermal fuse blew for a reason...dirty burner tube/burner/combustion-exhaust 'U' tube

If Electric works then need NEW Thermal Fuse before using gas
It is OK to run on electric because no flame is involved to blowback

Otherwise....
Bad spade connections on ECO
*on gas 12VDC goes to/thru ECO to gas valve
*on electric Millivolt goes thru ECO to gas valve to ground----allows ECO in temp control loop when using electric
(ECO...Energy Cut Off----Hihg temp T-stat)

Not the connections on ECO then circuit board but that would mean complete failure of board
*Blown 2A fuse on board

#1 suspect...Thermal Fuse blew

[flesslie]

Thanks for quick response. Everything looks good in outside panel, aged but in good shape. The fuse looked good but will check it better tomorrow along with all the other great suggestions in the daylight. Thanks again

[flesslie]

Update:
It was the Thermal Fuse Cut-off! I could not have figured without the great advice. Thanks everyone!

[Old-Biscuit]

Originally Posted by flesslie

Update:
It was the Thermal Fuse Cut-off! I could not have figured without the great advice. Thanks everyone!

Now clean the burner tube, orifice, combustion-exhaust 'U' tube so the thermal fuse doesn't blow again

Remove burner tube...sweep it out using small bottle brush and check that the 'spreader plate' is parallel with the end of burner tube
Unscrew the orifice from gas valve...soak in alcohol then air dry. No poking anything thru it or using High compressed air...damage it
'U' tube...push a piece of wire thru from combustion opening and out the exhaust port. Tie a rag to it and then pull it back out ...chimney sweep

[flesslie]

Thanks Old-Biscuit, got it cleaned up!
Y'all be safe out there!