Fridge Power Selection Mod

[jsutherl]

One of the problems with the whole house inverter that I installed in my Georgetown is that as soon as the power goes out (or somebody unplugs the motorhome) it switches to battery power. This isn’t a feature you can disable on my inverter, as far as I can tell. This is OK most of the time, in fact it’s a great feature when you’re onboard.

But when the motorhome is in storage I leave the satellite receiver DVR and refrigerator running on AC power. The DVR isn’t a big deal, it doesn’t draw much power, but the refrigerator draws about 35amps of 12VDC. That’d drain the batteries pretty fast if the motorhome lost power while in storage.

When I installed the inverter I installed a sub-panel for it so that I could break out the loads. For instance the roof top air conditioner circuits don’t go through the inverter. Unfortunately when Forest River wired the motorhome they chose to run the refrigerator off the same circuit that provides power to the outlets in the rear of the coach. So there was no way for me to separate out the power to the fridge when I did the inverter install.

Sometimes it’s nice to run the fridge on inverter. Like if you’re going to be driving all day. Then the engine alternator can easily provide the 35 Amps that the fridge needs and it saves you a bit of LP. It’s also nice if the fridge wouldn’t light or there was an LP problem.

So I determined to run a new circuit up from the main breaker panel to a switch. So that from inside the coach I can select Inverter power, regular power or no power at all to the fridge AC circuit. So that was last weekend’s project.

It started by running a new circuit under the motorhome from an unused breaker in the breaker panel at the back of the coach up to where I was going to put the switch next to the door. Then two pieces of romex from the old fridge outlet, one to carry power to the switch and one to carry it back. Then a new outlet in a nice box with enough room to make the connections.

I used romex for the inside parts and an outdoor rated extension cord wire for the run under the chassis. The switch is a machine rated 15A 250v switch. The switch is mounted in an all plastic box so hopefully I’ll never get a surprise shock from it.


P.S. Sorry about the mess in the photos. I hadn't yet cleaned up when I took them.