Hot Water Heater

[Raindem]

Hi. I'm trying to understand the HWH in my '98 Coach House. According to the owner's manual I have a LPG type. There is a rocker switch above the bed that the manual says is to turn on the HWH. Huh? What exactly does that switch do, and why does the manual say I can't run the A/C at the same time the HWH is working? HWH is propane. A/C is 110V.

Next, there is a switch near the sink that is labeled "Hot Water Heater". In the same switch plate there is a 110V outlet, but nothing is attached. Another "Huh?"

Finally, there is yet another switch on the stove hood that says "12V water heater".

So what is deal with these? The manual only talks about the LPG one. I haven't tried them yet, wanted to get some more info first.

Thanks

Curt

[obgraham]

I expect you have a dual fired HWH. Runs on propane, or electric, or both.

[Raindem]

Originally Posted by obgraham

I expect you have a dual fired HWH. Runs on propane, or electric, or both.

Not according to the model number. It's straight propane.

[AK49er]

Our hwh switch is also on the wall above the bed. Flip the rocker on and the red light will come on for a second then go out. The hwh does not have a pilot light, it is electronic ignition. Our manual does not say anything about A/C and hwh together. The only other switch above our hood is for a 12v fan that is placed behind refer to help cool it when temps are high. I suspect that previous owner added an additional electric element to your hwh for use with shore power, lots of folks have done that, the electrical kit is about 100.00. Lots of stuff isn't there?

[Raindem]

I'm starting to think they're just extra switches.

The switch above the bed worked just like you said. I turned it on, I could hear the propane heater ignite, and the light went out (but the heater kept working). Tested hot water at sink. Almost hot but not quite. At least I know it's working.

So I shut off the propane and turned on the generator, and tried the 110V HWH switch. No hot water. Nothing. Then tried the 12V, with and without the generator. Nothing.

I started digging around under the sink and found 2 loose wires. I tested them with a 12V test light and sure enough, they get 12V power when the 12V switch is on. So it's wired for a 12V HWH but not equipped with one.

I have no idea about the 110V swithc. It lights up when I turn it on but I have no idea what it goes to. I thought maybe it controlled the outlet next to it, but that has 110V whether the switch is on or off.

[AK49er]

I think that you could rule out the hwh being fed by 12v. The ones I have seen are 110 only, in addition to propane. After you turned off propane did you let the water cool down before trying the 110 switch? How did you determine it was not working? If I understand it right, you have power to the 12v switch and found wires leaving the switch that are hot when switch is on? I guess you could discontinue that set-up if you wanted or could try and trace them to wherever they went. Can you access the wires for the 110 outlet/switch and see where they are headed, maybe pull off the outside refer and vent panels to try and see the wires and where they go.

[Caped Crusader]

One of the switches might be your outside porch light.
The 110 plug would be there to use when on shore power, or if you have an inverter.

[Raindem]

After I tested the HWH with propane I drained the system and filled with fresh cold water. That's how I know the electrical switches aren't working. And they are clearly labeled. The 110V above the sink says "Hot Water Heater" and the 12V on the stove hood says "12V Hot Water".

I may get around some day to tracing those 110V wires to see what they go to. But for now I'll just assume I only have a propane HWH.

[obgraham]

Possibly the HWH you have now is not the original one -- it is, after all a 16 year old rig.