Atwood G8A-6E water heater problem

[Frodgesd]

I recently had a new refrigerator installed and the water hasn’t worked since.
When I turn my lp only remote switch on it blows the 2 amp fuse in the control board. I have 13-5 volts on the brown wire and the blue wire but that it. I checked the wiring on the remote switch and have a red wire instead of a brown and purple is the hot wire from the inverter that provides the power from the battery. I have tried two new circuit boards and they both have the same response. The igniter sparks but as soon as I touch the brown wire to the thermostat bar it blows the 2 amp fuse. It acts like there is a short but I have no idea where to start to find the short.

[javelin]

Welcome to the forum. Sounds like two problems (or more) going on. First off always provide the year and coach model and as many trouble details as possible so forum readers can assist you better.


Regarding the fridge problem.......is it a residential fridge and what water is not working any longer.....no water in the coach, no water for ice maker, etc.? If there is no water at the fridge, (assuming you had a new residential replacing an old residential), check under or behind the fridge for a water valve being in the off position. Contact the fridge installer and ask them for details on where the valve is located and confirm that they did actually reconnect a water line to the new fridge.


Regarding the water heater problem......is that the correct and complete Atwood model number? Also make sure you have the correct circuit board for the model of water heater. A fuse blowing on the control board does sound like a short circuit or abnormal current situation. Ensure that when the circuit board is physically mounted it does not short to ground somewhere on or around the mounting clips or touches chassis metal somewhere it is not supposed to be grounded. Check the electrical schematic that came in the manual for your specific model water heater and verify that all wiring follows the schematic. It might be worth calling a mobile RV tech to assist you since buying several circuit boards probably cost you that much already.

[16ACE27]

Originally Posted by Frodgesd

........and purple is the hot wire from the inverter that provides the power from the battery.

Wuuuuut?
What's an inverter got to do with the water heater? The only power from the battery that an inverter supplies is 120 VAC and the control power for your water heater is 12 VDC.

[OldWEB]

You sure the model is right? The first number is the size of the unit in gal. and I cannot find a 8 gal. WH.

[OldWEB]

Looking here, the 12V on the 'blue' wire is for the lockout light. I assume that works?
Now disconnect the 'red' wire to the ECO sw. and the wire to the 'spark & sense' and try connecting the brown to positive, or if you are low on fuses, place the ohmmeter leads on the 'brown' and 'green' wires to see when the "short" disappears. A short will show as less than 25 ohms let's say. Also some circuits matter if the red/black meter leads are one or the other wire, so try both ways (Red meter lead should go to the 'brown' wire.)

[Frodgesd]

You are correct about the model number. I put the numbers in the wrong order.
I will give that a try and see if I can see the short. And I think it is a short.
Thanks.

[OldWEB]

Now thinking about it (again), why is there 12V on the 'blue' wire if the circuit fuse blows? With a blown fuse, there can be NO volts anywhere after the brown wire. Maybe the short is in the blue wire circuit, that is, in the "Non-Ignition Light" circuit... remove the blue wire too. Good Luck

[Frodgesd]

Well I found the short and the cause. The short was a result of the wires in the control module pigtail and melted them together enough to expose the hot and ground wire together.
Once I separated them and taped the bare spots, it fired up land I noticed some flame and a lot of heat coming back out the bottom flue tube. I cleaned the tube and tried again with the same issue. I’m wondering if it’s the wrong burner tube because the exhaust at the top of the flue is barely warm and enough heat is coming back out the bottom that it’s melting wires which is what I think happens to start this mess. Just not sure what to do to get it corrected.

[OldWEB]

Originally Posted by Frodgesd

Well I found the short and the cause. The short was a result of the wires in the control module pigtail and melted them together enough to expose the hot and ground wire together.
Once I separated them and taped the bare spots, it fired up land I noticed some flame and a lot of heat coming back out the bottom flue tube. I cleaned the tube and tried again with the same issue. I’m wondering if it’s the wrong burner tube because the exhaust at the top of the flue is barely warm and enough heat is coming back out the bottom that it’s melting wires which is what I think happens to start this mess. Just not sure what to do to get it corrected.

Now it sounds like a blocked burner tube. :-/ Look online for YouTube vids.
https://www.airforums.com/forums/f44...be-214870.html

[mytimeyet]

Mud dauber wasps. They managed to close the entire burner tube. Shop-vac and a metal clothes hanger were the tools of the day.