Trouble starting the refrig

[wbmiller3]

This is probably obvious, but I just re-learned it. You have to have 12v power in the trailer for the fridge to work, even on propane. You can light it but it won't get cold if there is no 12v power.

What a time to find out I forgot to pull the radio fuse after the last trip. The radio switch is moving to the top of the improvement list!

So, I got to try out the "charge the battery with an idling vehicle" fix. After ~1.5 hours of idling the trailer battery was up to the 3rd LED on the gauge. It did not noticeably drop the TV fuel gauge.

Hideously inefficient, I'm sure, but plugging into shore power was not an option at the time in SE Houston, and generators are not to be found either. You do what you can.

Obviously, shore power's back on now.

[ShrimpBurrito]

Why do you need 12v to operate the fridge on propane? What part of the fridge consumes power?

Dave

This thread has taught me that there are many people out there that don't know how the fridge works.

[wbmiller3]

I don't know what part uses power, some control circuit? My battery was completely dead when I lit it and 2 hours later the temperature hadn't changed at all - I was feeling the little boltheads in the back of the freezer to see if anything was happening. As soon as I hooked up the truck (12v power on) they started getting cold, and it worked fine after that.

Edit - I just looked at the Dometic website and one of the manuals there says "The refridgeration controls will work down to 9.6v DC. A continuous 12v supply must be available for the electronic control to operate." This isn't the exact model I have, though.

We had an interesting event on our daughter's Dometic on a recent family outing. All worked well on shore power, but upon disconnect the battery was dead. When she went to start the refergerator on gas for the ride home (her non-TM model does not have 12v), the sparker wouldn't spark! Had to reconnect to shore power to get the sparker to work, then disconnect shore power and all was well. Apparently the sparker requires at least a little power to work. I had thought it was completely mechanical...

[Bill]

There are two kinds of sparkers - electronic and piezo-electric. Your daughter's rig apparently has an electronic sparker - a small circuit that generates a high voltage. This is the kind of sparker that's in the TM water heater for example, and in the TM furnace. Some Dometic refrigerators do, in fact, have electronic ignition.

A piezo-electric sparker is what you have in a gas barbeque grill, where there is certainly no electrical power. It is essentially a small hammer that strikes a small chunk of a piezo-electric material (quartz or similar). One of the properties of this material is that when deformed (by bending or smacking), it produces a small electrical charge. This is what we have in the TM refrigerator, and is also what a number of us have added to our TM stove/oven.

Did that make sense?

Bill

Great info - thanks for the replies - understanding how the sucker is supposed to work is half the battle.

Keith in Thousand Oaks, CA

Thanks Bill...who would have known there are different kinds of sparkers? Not me! The mind reels.

[Wavery]

The way that you can tell the difference is, the piezo type will give you one click when you depress the button. The electronic type will continue to spark (in rapid succession) as long as you hold the button down.

[B_and_D]

We have the Dometic model RM 2310 in our 1997 TM.

We can light it (to run on gas) without any power (AC or DC) and it cools down quickly and runs (on gas) without any power. I just went out tonight and tried it again. We sometimes pull the fuse from our TM when we are dry camping and going away from the campsite for the day to save battery power and this particular model runs just fine without any power.

I am scratching my head and wondering why Dometic chose to change their newer refrigerators to require battery power in order to run.

I like ours better; even with a dead battery you still can use the propane refrigerator.