Test spark, Dometic manual reefer

[Deb Mac]

Good afternoon all. Troubleshooting the fridge in my old Bigfoot. Dometic RM2401, manual piezoelectric 3-way. Runs great on 120V and will work well on gas - once you get it lit. Will light and run easily from the outside with a BBQ lighter. PO told me that the spark was intermittent. Now I am doing this on my own - can't push the button and run outside in time to see the spark (if any) For this same reason, I can't use the BBQ lighter to run my fridge on LP - usually travel solo. So, I am going to set my iphone up in the compartment, put the cover back on so everything is reasonably dark in there and video the attempt.

Of course, if I get no spark, I won't know if the problem could be with the electrode or the lighter itself. My thought is to disconnect the lighter from the electrode and place the spade connector close to something metal (like the gas line - gas is OFF BTW) and see if I get a spark from there. If I do, then I know the problem is the electrode. If I don't.....

Edit: Well I do get a spark, but it seems pretty puny. Not sure exactly how vigourous it SHOULD be, but it does seem inconsistent. One was pretty solid, one looked weak and the other was somewhere in the middle. So I am thinking it's the electrode, or the connection thereto. Though continuing to hunt for a replacement fridge if a decent one comes up.

Thanks for any and all suggestions. I am also keeping my eye out for a replacement - either a 2410 or 2501.

[ZachO]

I've never been able to check how large my spark was, either. I usually camp solo too. I would guess it's a pretty small spark. Maybe compare it to the bbq lighters spark?

You could try gently cleaning the connections. How does it act when it won't light? You keeping pushing the spark button and get no flame?

My flame always lights, it's getting it to stay lit that causes me issues.

[John in Michigan]

The manual for my Dometic RM360 fridge says this:

The Electrode
For a proper ignition function it is necessary to keep the
electrode insulation dry and free from dirt The gap between
burner tube and electrode shall be max. 3/16" (5 mm) and min.
1/8" (3 mm).

[John in Michigan]

Also, much more detail provided at the link below on Dometic refrigerator flame troubleshooting.

https://www.arprv.com/dometic-fridge-flame.php

[gordon2]

Good links John.. it seems that the most common cause of poor sparking is the gap distance. But I had to laugh because I did the same thing - using video to watch the spark. Its sounds like the OPs case is pretty normal. In my case I figured out the spark was OK its just that it took so long for the gas work its way almost all the way around the camper that it seemed like it was not working right.

[Lynn Eberhardt]

If the propane has been off for a while, light the stove to get gas flowing in the lines before lighting the fridge.

[Deb Mac]

Thank you for all of the info & the links. I can't test the lighting at this point because the propane is off (removed the old gas water heater and have to get to the hardware store to pick up valves and caps). I am going by what the previous owner told me. So I thought I would start by checking to see if there was a spark.

I am going to clean it all up (rust in a number of places - burner looks like it has seen better days) before I turn everything back on and try again. But thanks for the suggestion regarding starting with the stove. And I suspect that the gap may be off as well. That electrode does look pretty grimy. I set it up for 120V and it worked great.

So I will start with a good cleaning, check the connection at the spade connector, check the gap and try again (once I get those 2 un-used interior propane lines capped). Cheers

[John in Michigan]

Also keep in mind that if you are lighting the fridge immediately after opening the gas valve at the tank, it may take quite some time for gas to reach the fridge while you are holding down the prime button. A trick some people use is to light the stove burner first (easier to light), then turn off the stove, then light the fridge.

[ZachO]

Ah, so you haven't actually tried it on gas yourself yet?

In that case, you might be in for some fun.

What you're planning to do will definitely help. Get everything cleaned up (including the gas orifice), and see how it goes when you can turn the gas back on. Gas in the lines or not, my fridge can be pretty stubborn. It's not uncommon for it to take up to 5 minutes to stay lit. This doesn't sound like that long, but when you're hunched over holding the gas valve button in, it gets old.

The progression goes: It'll light right away with the spark, then go right out. I light it again and again, and it'll stay on longer and longer while holding the gas button in, but will go out immediately if I let the button out even after holding the gas button in for up to a minute. Eventually, it'll finally stay lit.

My reason for sharing that is only because a less experienced or patient person could be forgiven for giving up, saying "the fridge doesn't work, it won't stay lit", not realizing it just takes work, but it'll always light. At least so far mine will always light...

[John in Michigan]

Also per my Dometic RM360 manual, if equipped with piezo lighter:

After the gas is lit keep the button C pushed for 10 seconds. Release the button and check through the reflector that the burner flame stays burning. If not repeat the lighting procedure.

[gordon2]

Originally Posted by Lynn Eberhardt

If the propane has been off for a while, light the stove to get gas flowing in the lines before lighting the fridge.

Originally Posted by John in Michigan

... A trick some people use is to light the stove burner first (easier to light), then turn off the stove, then light the fridge.

Works great if your stove is downstream from the fridge, or close to it.. but YMMV... in my camper the stove comes first, then there is maybe 12 more feet of gas line... down the port side, across the back, and more than halfway up the starboard side to the fridge. Lighting the stove only gets gas through about 20 percent of the distance to the fridge.

If you hold the gas valve in without trying to ignite it, in order to get the air purged out and gas to the fridge (not my official advice BTW), then give it extra time to clear out any gas that might have been released. Only then open the valve again (push button) and hit the igniter right away, within 2-3 seconds.