Community Forums

rshackleford · 08-09-2014, 06:47 PM

My hot water heater quit working on lp. Works fine on ac. Where should I start troubleshooting?

Tomtall · 08-09-2014, 07:19 PM

When you activate the LP switch you should first here your gas valve go "click" a very short time later you should here the igniter fire off. Are you hearing that happen?

Oh ya might sound silly but your propane tank does has fuel in it,right?

SteveLevin · 08-09-2014, 10:22 PM

Let me toss one other "ah ha" thought out there. In my coach, in the basement on the internal "wall" where the water heater is, mine has two toggles -- one for gas and one for electric (that is, using those switches, I can "force" one mode or the other, or use both). If yours is similar, make sure nothing has accidentally bumped the LP toggle to the off position.

Beyond that, assuming your gas is working at the stove, etc., I don't know enough of where to point you -- do you hear it trying to ignite, or igniting and then turning right off?

Steve

Pexring · 08-09-2014, 10:25 PM

You should hear a fast click-click-click coming from the ignitor board. If you don't hear that, you might have issues with that ignitor board. A good RV place would be able to test it for you if you bring it in.

Mark

Just For Fun · 08-09-2014, 10:45 PM

Quote:

Originally Posted by rshackleford

My hot water heater quit working on lp. Works fine on ac. Where should I start troubleshooting?

I have a similar problem that seems to be building. Possible similar to yours.

Igniter works intermittently. So we began using a long-nose lighter to ignite the flowing LP. Now when it ignites, it will only run for about 3/4 seconds and then the LP flow (we can no longer hear the hissssssing sound of the LP flowing) stops and obviously the flame disappears.

Are you seeing the same thing?

Skip426 · 08-09-2014, 11:04 PM

Quote:

Originally Posted by rshackleford

My hot water heater quit working on lp. Works fine on ac. Where should I start troubleshooting?

Do you have the owners manual with the troubleshooting guide ?

If not there is info in the " Files " drop box , just to the right of your " User CP"

All contacts of the igniter have to be clean , the gas solenoid wiring has to be properly grounded. Newer W/H use the igniter wire from the control board to the tip as a heat sensor to keep the gas on so things have to be clean , carbon build up on the tip can dissipate heat too quickly and the control board will shut the gas off , because it thinks the flame is out.
Other info here.

Chaffeekid · 08-11-2014, 05:23 AM

Turn the switch off at the control panel. Then remove and clean each connector to the control board, the ECO and the T Stat. Clean them with a RED rubber eraser, the big rectangle type works the best. Move the ECO and Tstat back and forth a few times just to break any corrosion that may have built up on these sensors.

If you have the edge card connector on your heater control board, make sure the fingers on the edge card are clean, you may have to use contact cleaner if any corrosion is noted.

I did all this and still had the same problem, and ended up replacing my control board.

Atwood RV Water Heater Ignition Module All Models | eBay

This is the cheapest one I found on E-Bay, most RV places want close to 200 for the board. Or you might luck out and find a used one on Craigslist, but remember someone took it off cause the heater probably didn't work, unless they were scrapping the unit.
Hope this helps
Jim
oh and look a couple of pages down for atwood 6 gallon heater, mine, which turned out to be a 10 gallon for some other tips.

Chaffeekid · 08-11-2014, 08:21 AM

Also you will notice a fuse attached to the T-Stat via a red wire that runs back to the control board. Unplug this fuse to break any corrosion and if you have an ohm meter check that there is continuity thru the fuse.
No ohm meter, hook the red wire directly to the T-Stat minus the fuse and see if the heater lights, if it does, do not leave it connected this way, get another fuse and hook it up. The fuse is there in case the water heater over heats. It is a thermal fuse and will prevent a fire by shutting off the gas supply via the ECO.
Hope this helps
Jim

rshackleford · 08-11-2014, 12:16 PM

I'm back home now at a point where I can troubleshoot. Already tried bypassing the overtemp fuse, no luck. Going to try cleaning the connections and the gas line

Tom-NC · 08-11-2014, 12:34 PM

Hi,

Check the orifice by the chimney. Sometimes rust falls down from the chimney and plugs it up. All you have to do is use an air to blow out all the rust and you should be good to go. If relay is clicked that means it is ok and allowing gas to flow but since no ignition it shuts off the gas.

Hope this helps.

Chaffeekid · 08-11-2014, 02:06 PM

Also pull the igniter out, usually one screw at the bottom of the flue, and if you have only one wire going to the control board, with steel wool clean the probe that is sticking out from the Igniter, and the ground probe.
This one wire igniter is also a sensor that tells the board that the flame is on. Clean it with steel wool and set the gap to 1/8" that is what my book calls for. If you have two wires, one is for the igniter and one for the probe. In any case, clean both with steel wool. Tom NC had good advice also, but when you blow out the flue, do it from the flame area and make sure you are not around the exhaust or you might get a face full of rust and debris. Don't ask how I know this.

Experience is my way of finding out what doesn't work

Jim

rshackleford · 08-11-2014, 05:04 PM

Thanks for all the replies. Looks like it is an issue with the Eco. I'm not sure how it is supposed to connect to the tank but it seems loose. If I hold it in so the back of it is touching the tank then it lights and works fine.
Is the Eco and t-stat a single unit? Do they attach to a mounting plate or something?

Chaffeekid · 08-14-2014, 05:23 AM

Take a good look at the ECO and T-stat. The are held on by spring pressure. It probably has a rubber sheet over the top of it held on by glue. You will have to pull this off.
The ECO and TSTAT can be rotated and taken off. They are held in contact with the heater by spring pressure. Just rotate them so the gap in the plastic washer lines up with a tab so you can remove it. These are available on E-bay or at your local RV store if you are near one, for around 20 bucks.
However, as you describe it the ECO probably has corrosion built up on it and needs to be cleaned. I used 00 steel wool to clean mine, and the mounting surface on the heater.
Hope this helps
Jim