Atwood Water Heater Switch

[7months14day]

atwood GC6AA-10E 6 gal water heater , i have replaced thermostat , igniter , flushed tank, and cleaned burn tube in water heater . It fired up nice i adjusted flame looks and works great but when i turn it off and turn the electric WH switch on the gas burner fires up. So please help. also i turned gas off at tank and when it burned out, after an hour the water was really hot so the element definitely works. Just an old retired mm no pro. Thanks much

[Old-Biscuit]

10E in model number means it uses the same DC Power Source, Same set of t-stats and same circuit board
DC Relay triggers 120V AC to element which is fed from a AC Circuit Breaker

Should have a Dual On/Off Switch ....
One switch for electric element function
One switch for propane function

One Main DC Power comes from a FUSED DC SOURCE to the dual switches.
First to one of the on/off and then jumpered to the other on/off switch

(If RV MFG didn't use Atwood OEM Dual Switches then RV MFG could have wired it 'their' way.)

From the on/off switches each heating function uses separate wires to the circuit board.........but use same circuits for thermal fuse/T-stat (Brown wires) then ECO (Red wires)
Circuit board then splits heating control between electric, propane OR both at same time (both on/off switches ON)

When turning electric ON.........propane also fires up (switch still off)?
Then switches are shorting across OR shorting across at upper pin connector on circuit board (WHITE Wire/Electric---ORANGE Wire/Propane)

As for normal temps...whether using electric or propane
T-stat (normal temp control t-stat) OPENS when water temp reaches 140*F ----CLOSES so heating can resume when water temp reaches >110*F
ECO (Energy Cut Off/HI Temp t-stat) OPENS at 180*F to shut ALL heating down (Safety feature) Will reset when temp >150*F
*ECO Opens....RED Fault Light on OEM Dual Switch Panel. Heating 'locked out' have to turn switch(es) OFF wait 30 seconds turn ON for continue heating cycles
**ECO Opens.......then T-stat (normal temp) FAILED---loose/not tight to tank or bad


Thermal Fuse (clear tubing---Brown wire to t-stat) is a one shot safety device. BLOWS if senses 190*F ----blow back for propane flame coming out of combustion chamber (blocked/obstructed combustion/exhaust ---mud dabbers/nest etc)
If blown have to buy new and replace it

Dual On/Off Switches (or TWO separate switches)......wiring


Atwood Water Heater Wiring Diagram (from On/Off Switches to circuit board)



Hope I haven't confused you?

[John Boy]

Originally Posted by Old-Biscuit

10E in model number means it uses the same DC Power Source, Same set of t-stats and same circuit board
DC Relay triggers 120V AC to element which is fed from a AC Circuit Breaker

Should have a Dual On/Off Switch ....
One switch for electric element function
One switch for propane function

One Main DC Power comes from a FUSED DC SOURCE to the dual switches.
First to one of the on/off and then jumpered to the other on/off switch

(If RV MFG didn't use Atwood OEM Dual Switches then RV MFG could have wired it 'their' way.)

From the on/off switches each heating function uses separate wires to the circuit board.........but use same circuits for thermal fuse/T-stat (Brown wires) then ECO (Red wires)
Circuit board then splits heating control between electric, propane OR both at same time (both on/off switches ON)

When turning electric ON.........propane also fires up (switch still off)?
Then switches are shorting across OR shorting across at upper pin connector on circuit board (WHITE Wire/Electric---ORANGE Wire/Propane)

As for normal temps...whether using electric or propane
T-stat (normal temp control t-stat) OPENS when water temp reaches 140*F ----CLOSES so heating can resume when water temp reaches >110*F
ECO (Energy Cut Off/HI Temp t-stat) OPENS at 180*F to shut ALL heating down (Safety feature) Will reset when temp >150*F
*ECO Opens....RED Fault Light on OEM Dual Switch Panel. Heating 'locked out' have to turn switch(es) OFF wait 30 seconds turn ON for continue heating cycles
**ECO Opens.......then T-stat (normal temp) FAILED---loose/not tight to tank or bad


Thermal Fuse (clear tubing---Brown wire to t-stat) is a one shot safety device. BLOWS if senses 190*F ----blow back for propane flame coming out of combustion chamber (blocked/obstructed combustion/exhaust ---mud dabbers/nest etc)
If blown have to buy new and replace it

Dual On/Off Switches (or TWO separate switches)......wiring


Atwood Water Heater Wiring Diagram (from On/Off Switches to circuit board)



Hope I haven't confused you?

Just wanted to jump in here and say Thank You for helping me figure out my water heater about a month ago. Not related to this post. John

[7months14day]

Thanks for your help. If i turn on the electric remote switch the propane circuit also energizes. With a test light i get power at both the white and orange wires. Electric switch off and propane switch on, i get power at only the orange wire. With wires disconnected from the circuit block, i get continuity through both terminals Is it safe to assume the circuit block needs replacing? It is an atwood circuit block. Thank you very much

[Old-Biscuit]

Originally Posted by 7months14day

Thanks for your help. If i turn on the electric remote switch the propane circuit also energizes. With a test light i get power at both the white and orange wires. Electric switch off and propane switch on, i get power at only the orange wire. With wires disconnected from the circuit block, i get continuity through both terminals Is it safe to assume the circuit block needs replacing? It is an atwood circuit block. Thank you very much

Not sure what you mean by 'circuit block' ?

Do you have the Atwood OEM Dual Switch ?
OR
Has RV MFG provided different switches for electric/propane?

Pictures of circuit block//switches would help

Electric should NOT energize electric AND propane ----

[7months14day]

It does have electric switch and gas switch blackwater grey water and so on. The block is the black box on the outside of unit with wire plugs going to it . Sorry i don't know how to send pictures and don't know what that box is called but had it replaced about a year ago, the 3rd pin on it was not open circuit the 2nd one was and was thinking it was bad thank you

[7months14day]

circuit board

[Old-Biscuit]

OK Circuit Board..........

With top connect pulled off circuit board
Test voltage on following PINS in connector
With Propane switch ON (electric OFF) ----voltmeter neg lead on GREEN wire pin and pos lead on ORANGE wire pin (should be 12V DC +)
Move pos lead to WHITE wire pin......no voltage

Electric ON (propane OFF)----voltmeter neg lead on GREEN wire pin and pos lead on WHITE wire pin (12V DC+)
Move pos lead to ORANGE wire pin ---no voltage
If you do read voltage then issue is NOT with circuit board but back at On/Off Switches


TO properly TEST circuit board 'tracks' for continuity requires circuit board be REMOVED prior to testing
Then you can test 'power track'
Voltmeter set to OHMS
Neg lead on Ground (GREEN wire contact on edge connection of circuit board
Pos lead on Power (TOP BROWN wire contact on edge connection of circuit board)
NO CONTINUITY-----circuit board is defective


Post results......


As a side note: WHY did you replace circuit board before???

[7months14day]

circuit board melted wouldn't work replaced and worded fine for about a year until this time.Will get back tomorrow thank you very much

[7months14day]

actually i did have enough day light. everything checked out, propane on electric off , green and orange 12+, white pin no voltage, Electric on propane off , green and white 12+ pos to orange no voltage circuit board tracks test green and brown 9.95 OHMS everything looks good thank you thanks for your patients. Im bumpuzzled

[Old-Biscuit]

Originally Posted by 7months14day

actually i did have enough day light. everything checked out, propane on electric off , green and orange 12+, white pin no voltage, Electric on propane off , green and white 12+ pos to orange no voltage circuit board tracks test green and brown 9.95 OHMS everything looks good thank you thanks for your patients. Im bumpuzzled

You are not the only one

With those results there is NOTHING that points to propane being energized when using the electric

With connector back on circuit board....
Turn electric ON
Then using a sharp probe....measure voltage on ORANGE wire ?

Also measure voltage on at ECO on red wire going to gas valve
(when on electric there will be millivolts thru ECO in order for ECO to be part of control scheme. On propane it has FULL DC voltage thru ECO)

***Propane firing off when electric used sure does make it sound like bad power track on circuit board---even though power test showed continuity.'

[7months14day]

with electric on orange wire 12.2 volts, voltage on red wire gas valve to eco 0, on propane it has (0) voltage through eco thanks much ???

[Old-Biscuit]

Originally Posted by 7months14day

with electric on orange wire 12.2 volts, voltage on red wire gas valve to eco 0, on propane it has (0) voltage through eco thanks much ???

With the top connector pulled off of circuit board.......

TEST
Electric ON.......voltage on WHITE wire PIN to Ground
Then check for any Voltage on ORANGE Wire PIN to ground

Get voltage reading on ORANGE PIN..........On/Off Switches are shorting across

No Voltage on ORANGE....circuit board is shorting across on edge connector or internal

[7months14day]

with the top connector pulled off of circuit board. with electric on voltage on white wire pin to ground 13.1 volts , 0 voltage on orange pin to ground. connector looks good no frayed wires , so i should order a circuit board ? i tend to agree with you. I will post when i get it and installed. I have confidence in you and this forum. You are the best!!!!! . thanks much 4K and 6K linear fiber laser cutters