Atwood Water Heater Blues

[eazrider]

2003 Itasca Horizon 36LD
Recently tried to activate the water heater ( ( Atwood GCH 10A-3E) has both electric AND propane capability.. Tank has water...No spark at automatic ignition after turning water heater "on" nor will the electric function heat water ( connected to 30A pedestal) Checked breaker at the foot of the bed, also, " water heater " switch ( for electrcal functionality?) No clue why either mode will not heat. Any thoughts..?

[shootist]

Needs 12v as well. Check fuse etc

[Old-Biscuit]

Atwood GCH 10A-3E uses separate controls for Gas and Electric so you have 2 issues....one DC for Gas and one AC for Electric

Gas uses 12VDC from a Fused Source to the On/Off Switch
From Switch DC goes to Thermal Fuse (clear tubing) to/thru T-stat to Circuit Board via BROWN wire
T-stat closes for heating at 110*F....opens stopping heating at 140*F
From circuit board with t-stat closed DC goes to/thru ECO to Gas Valve
and Spark Electrode for ignition

So verify you have 12VDC to/from Switch and on BROWN wire
Could be blown Source Fuse, Bad 2a fuse on circuit board, blown Thermal Fuse (blows at 190*F) or T-stat not closed


Electric uses 120VAC from 15A Circuit Breaker to On/Off switch then to/thru T-stat then to/thru ECO to Element
OEM On/Off switch is on backside of Water Heater Tank on the protective cover over the set of t-stats and element
ECO is a Manual Reset if tripped.......small hole in cover-use pencil to push in the reset button on the ECO via the hole

IF you have an On/Off Switch inside the RV that is in addition (RV MFG) to the Atwood OEM switch and is wired in series with OEM---both have to be ON
Check 15A CB....verify you have 120VAC to/thru switch(es) , check if ECO has tripped/manual reset
Element could be burnt out......dry fire and they burn out
*Black & White wires removed...continuity between black & white terminals. No continuity...burnt out
Continuity test between White terminal and Element Flange.....continuity then element is shorted

Models prior to 2004.....6 gal/10 gal use same wiring diagram

Here is the 12VDC


Here is the 120VAC

[Duner]

Check the 12v relay on the back side of the tank. There's a ground wire that connects to stud on the tank and that nut might be loose. That was the problem I had on my 2004 Winnie a few years ago.
Good luck,
Bill

[Sam 3]

Light up your stove top. If your regulator and hoses are old they might need to be replaced. Utube should have a tutorial for you to look at. Others have given you some good advice(fuses).

[Old-Biscuit]

Originally Posted by Duner

Check the 12v relay on the back side of the tank. There's a ground wire that connects to stud on the tank and that nut might be loose. That was the problem I had on my 2004 Winnie a few years ago.
Good luck,
Bill

OPs 3E version does NOT have/use the DC Relay.
Electric is direct
Gas/Electric are separate and have their own controls

[DancinCampers]

On the electric side I would also check that the EMS has not shed the load.

[eazrider]

Thank you guys SO much. Lots of tips to run down..
Might take a few days to get back on it, but will post progress...

[AFChap]

In that year coach the most common reason for what you describe is the fusible link due to poor air circulation behind the doesn't doors. Very easy to test by removing the link & connecting the wires together w\o the link. DO NOT operate the water heater w\o a fusible link in place as that is what turns off the gas flow of a flashback occurs, which I have also experienced. I carry extras, and did what I could to improve the air circulation behind the metal door.

[Old-Biscuit]

Originally Posted by AFChap

In that year coach the most common reason for what you describe is the fusible link due to poor air circulation behind the doesn't doors. Very easy to test by removing the link & connecting the wires together w\o the link. DO NOT operate the water heater w\o a fusible link in place as that is what turns off the gas flow of a flashback occurs, which I have also experienced. I carry extras, and did what I could to improve the air circulation behind the metal door.

That would affect gas side.............electric side is another issue

[eazrider]

Guys, finally got on/partially solved the " no hot water" issue. As suggested, I checked 12V DC from the switch down to the thermal fuse. No dc on the output side of the thermal fuse. I bypassed the thermal fuse ( just to see if that solved the problem) and " click" igniter started sparking, and " click" solenoid for gas flow opened. I have a " thermal fuse" ( plus spares) on order. Have not tackled the AC side of the problem, as , to be honest, never tried to use the AC heating element. Is there a switch that controls AC heat vs propane for heating water..? The only switches I can find are the one on the electrical info panel inside the coach, ( rocker switch turning " water heater on") and a toggle switch marked " Water Heater "On" or " Off" inside the area where a washer/dryer would be IF I had one. Turning that switch on appears to do nothing as far as I can tell.
Thanks again for the responses and excellent guidance..

[eazrider]

Originally Posted by Old-Biscuit

Atwood GCH 10A-3E uses separate controls for Gas and Electric so you have 2 issues....one DC for Gas and one AC for Electric

Gas uses 12VDC from a Fused Source to the On/Off Switch
From Switch DC goes to Thermal Fuse (clear tubing) to/thru T-stat to Circuit Board via BROWN wire
T-stat closes for heating at 110*F....opens stopping heating at 140*F
From circuit board with t-stat closed DC goes to/thru ECO to Gas Valve
and Spark Electrode for ignition

So verify you have 12VDC to/from Switch and on BROWN wire
Could be blown Source Fuse, Bad 2a fuse on circuit board, blown Thermal Fuse (blows at 190*F) or T-stat not closed


Electric uses 120VAC from 15A Circuit Breaker to On/Off switch then to/thru T-stat then to/thru ECO to Element
OEM On/Off switch is on backside of Water Heater Tank on the protective cover over the set of t-stats and element
ECO is a Manual Reset if tripped.......small hole in cover-use pencil to push in the reset button on the ECO via the hole

IF you have an On/Off Switch inside the RV that is in addition (RV MFG) to the Atwood OEM switch and is wired in series with OEM---both have to be ON
Check 15A CB....verify you have 120VAC to/thru switch(es) , check if ECO has tripped/manual reset
Element could be burnt out......dry fire and they burn out
*Black & White wires removed...continuity between black & white terminals. No continuity...burnt out
Continuity test between White terminal and Element Flange.....continuity then element is shorted

Models prior to 2004.....6 gal/10 gal use same wiring diagram

Here is the 12VDC


Here is the 120VAC

Thank you " Old Biscuit", for the excellent trouble shooting directions..

[Old-Biscuit]

Originally Posted by eazrider

Guys, finally got on/partially solved the " no hot water" issue. As suggested, I checked 12V DC from the switch down to the thermal fuse. No dc on the output side of the thermal fuse. I bypassed the thermal fuse ( just to see if that solved the problem) and " click" igniter started sparking, and " click" solenoid for gas flow opened. I have a " thermal fuse" ( plus spares) on order. Have not tackled the AC side of the problem, as , to be honest, never tried to use the AC heating element. Is there a switch that controls AC heat vs propane for heating water..? The only switches I can find are the one on the electrical info panel inside the coach, ( rocker switch turning " water heater on") and a toggle switch marked " Water Heater "On" or " Off" inside the area where a washer/dryer would be IF I had one. Turning that switch on appears to do nothing as far as I can tell.
Thanks again for the responses and excellent guidance..

Electric uses 120VAC from 15A Circuit Breaker to On/Off switch then to/thru T-stat then to/thru ECO to Element
OEM On/Off switch is on backside of Water Heater Tank on the protective cover over the set of t-stats and element
ECO is a Manual Reset if tripped.......small hole in cover-use pencil to push in the reset button on the ECO via the hole

IF you have an On/Off Switch inside the RV that is in addition (RV MFG) to the Atwood OEM switch and is wired in series with OEM---both have to be ON
Check 15A CB....verify you have 120VAC to/thru switch(es) , check if ECO has tripped/manual reset
Element could be burnt out......dry fire and they burn out
*Black & White wires removed...continuity between black & white terminals. No continuity...burnt out
Continuity test between White terminal and Element Flange.....continuity then element is shorted