Dometic RM2652 no power to upper control board

[rvman69]

This is a Dometic RM2652 about a 2010 maybe a little older. I just got done putting in a rebuilt cooling unit. Before I put the cooling unit in I could turn the power button on the control panel on and the LED light would come on. Well after I got the new cooling unit in and the fridge back in its place and all hooked up. When I turn the light switch on I get no LED light like there is no power there. There is no heating element in it at this time. Pretty sure it should work on gas without having heating element installed. I do get 12 volts from the power lug up to the thermal breaker and across it. Then from there to board in back. The light in the fridge does work. It's like it is not getting 12v up to the upper control board. What is the best way for me to test power getting up to the upper control board? I was careful with the wires that go up to the top of the fridge and inside. But anything can happen I guess. Thanks

[dougrainer]

This system, the Reignitor does just ONE thing.
When the control module sends the Reignitor a 12 volt signal, it just sends the Electrode a spark current. Thats IT.
On this system, the control board,
1. sends a 12 volt signal to OPEN the gas valve
2. RECEIVES the FLAME signal LIT/ON Thru the standard Thermocoupler, then the control board removes the 12 volt power to the reignitor BUT leaves 12 volts to the gas valve.
This system also has a 3 attempt Gas lighting sequence. After 3 attempts it will lock out and turn on the CHECK light on the inside control board.
You can use a 16 or 18 gauge wire(12 inches long or so and strip both ends 1/4 inch. Stab one end of wire into the spade area of the Reignitor and hold the other end(insulated needle nose pliers) about 1/2 inch from a ground source. IF the Reignitor is good you will see a spark.
LAST, either for this thread or another a few months ago, I attempted to find a reignitor. NONE. I did find an aftermarket brand, but did not pursue getting it. Doug

[bigfootford]

Ok we got the noise thing sorted out..hahahaa.

The Igniter has three jobs!
1 Produce a spark

2. Wait to sense that there is a flame, if no flame for about 30 seconds you will get a check light. Not sure if the igniter does mutiple sparks in this situation.

3. Sense that there is a constant flame. This allows the Thermocouple
to warm up and produce a small voltage on it's wires that attach to the control board. A lost of flame from wind or loss of propane it will be detected/sensed and cause a retry, 'spark" to relight. If no flame is sensed after the retry the thermocouple will cool and a check light occurs.

A note, the Dinosaur board does an attempted recovery from a flame out due to wind etc it will retry XX times before it stops and lights the check light.

The sense of flame is the Igniter sensing a small current flowing from the burner, through the flame to the electrode then up the wire to the Igniter! The flame actually produces the small current!


I'm unsure if we can hear a good igniter make a sound with the electrode wire disconnected from the Igniter.

Replacement is going to be problematic from what I have researched.


This one is the only one I have found and the Vendor list of Dometic fridges does not include our 2652's.... You might contact them and ask if it will work.

I doubt it but might be worth a try. Expensive though.

https://www.ebay.com/itm/164674934043

I can not imagine that there are no igniters avail for this fridge. Found none online.

I called our local Camping World and they have none. Not very helpful.

Called a local Trailer and RV parts... They have them in stock $47.81

They do not ship... 😞

I think you will need one... I would contact a RV parts and service near where you live and see if they have them....

Jim.

[rvman69]

Also I forgot to say right before I took the camper to the campground I checked both the old and new electrode's for continuity from the end of wire to the tip of electrode and got 0 ohm reading on both. I have the original electrode here still so I guess I could check continuity from end of wire to the metal tab on electrode to make sure it is not shorted out. I should be able to go out to campground this evening or tomorrow to do more testing if I need to. Thanks

[rvman69]

Jim, let me ask this. If the reignitor is like it is in this pic with the electrode wire unhooked and way away from it. Should I hear any noise from the reignitor when the main board sends the 12v to the reignitor? Because I do. The best I can describe it is a wee wee wee. Not a snap snap snap. Any time I have got the electrode to spark at all it has had to be real close to the burner and it has not been a snap snap snap like I would expect. The same when I did the test with a screwdriver. It was more like a faint click click click. With a real faint spark. I wonder if the reignitor could be internally shorted and is not sending the voltage to the electrode that it should. I do definitely here a noise coming from the reignitor when there is no electrode hooked to it. I also here that same noise coming from the reignitor when the electrode is hooked to it. The noise from the reignitor is the same with or without electrode hooked up. I have watched videos of other people working on there electrode or replacing it and I have never got a spark like I see on there's. I am thinking maybe with my original electrode it was to far away to the burner at the factory setting to spark at the lower voltage it was getting. Then when I put the new one in it was real close to the burner and that is why I got the little sparking that I got. What are your thoughts? If it is a bad reignitor I hope I can actually find one. If it is say the coil covering in the reignitor has cracked I wonder if it could be fixed like you can fix arcade monitors and old TVs with sealant. Just a thought. Thanks

[bigfootford]

rvman69 wrote:
Jim, Just to be clear. I did hear the ignitor snapping/pulsing with the ignitor plugged in and also with it unplugged. On the last part of your last post when you said (If you have 0 ohms on the igniter wire to the electrode and the screw that retains the cerramic tip is tight, and do not hear the snapping then the wire has a short somewhere there at the screw.) Is the snapping you are talking about at the electrode(spark)? Not pulsing at the ignitor. Thanks

You say that you hear the NOISE both with the electrode wire connected and the electrode is screwed tight and in position but you see no spark and you hear the NOISE with the electrode wire disconnected from the igniter.....

Are the sounds different or the same? Arc is a snap , not sure what the pulsing is you're talking about.

Do the ohms measurement. Disconnect the Electrode wire and measure the resistance from the connector to the electrode tip... Should show 0 ohms.
Then measure the resistance from the electrode wire, still disconnected, to the little tab that the screw holds the electrode ceramic to the burner frame . Make sure the screw is holding the tab tightly to the burner frame. You should see no connection thus no meter reading.

We know that the control board is working because you said that you saw 12vdc on the Solenoid.... I THINK you said you can hear the solenoid click on. It should stay on and then click off after about 3 seconds.

Jim.

[rvman69]

Jim, Just to be clear. I did hear the ignitor snapping/pulsing with the ignitor plugged in and also with it unplugged. On the last part of your last post when you said (If you have 0 ohms on the igniter wire to the electrode and the screw that retains the cerramic tip is tight, and do not hear the snapping then the wire has a short somewhere there at the screw.) Is the snapping you are talking about at the electrode(spark)? Not pulsing at the ignitor. Thanks

[bigfootford]

Oops sorry. Glad you asked the question about the igniter pulsing.
When you disconnect the electrode wire from the igniter and hear the clicking it would mean that the electrode wire has a short.

I will correct my post...

You can tell if the electrode wire is open (no connection) or has connection to the electrode with your DVM.
There should be a near "0" resistance reading measuring from the igniter connector wire to the electrode. Set your dvm on 200 ohms scale... Touch the DVM leads together, you should read almost 0 ohms. Then do the connector on the wire to the electrode tip. Should read near 0 ohms.

If the electrode wire was open, no connection then you should hear the igniter clicking/snapping.

If you have 0 ohms on the igniter wire to the electrode and the screw that retains the cerramic tip is tight, and do not hear the snapping then the wire has a short somewhere there at the screw.

Jim.

[rvman69]

I was camping all weekend and did not have any time to look at the fridge any. Always something going on. The bad thing was the first full day there we had a storm roll thru and lost power. I was like here we go. No propane operation so fridge is not operating. It was only off 30 minutes thank goodness. Does the electrode look ok to you guys.
Jim, you said to disconnect the electrode from the reignitor and see if I still here the noise. You said if I dont it means the electrode has a short in wiring or from contamination. With the electrode unplugged should the reignitor not make any noise like pulsing. Because when I did the test with screwdriver up to it and got a spark (could not tell how good of spark). When I pulled the screwdriver way away I could still here the reignitor pulsing. Could that mean it is shorting out inside? Just wanting to get this figured out so i have some peace of mind. Thanks

[rvman69]

I have posted some photos on here before but something was going on earlier. It seems like it will let me do it now. I dont know if they were working on the site or something. Thanks

[bigfootford]

Ok, here is the picture posting link, designed by one of our RV.net folks.
You will have to add it to your web links/favorites so you can use it whenever you want.
If you do not then you will have to find the website every time to post a picture.

Bummer that the RV.net website software does not work like most typical webs when you want to post a pix. We have asked for a change for 20 years, no kidding!

So use the link below....

The app will give you the URL to post, just copy it and post it in your Post text.

You need to copy and paste this URL on a different tab...Ugg tab? Otherwise you will not be redirected to this link and you will loose your RV.net web tab... Sucks.
Hope you can understand the steps.

Once you have done this save the URL into your favorites!

http://photoposting.is-great.net/?i=2

Find your picture.

Select it.

Copy the url that the app gives you and post it into your text of the post.

Sorry if It is not real clear.

Jim.

[bigfootford]

rvman69 wrote:
I used my Fluke meter and got 13.2v at the 12v block. Then I got 13.2v at the yellow wire going into the reignitor with the yellow wire plugged in. I could here the reignitor pulsing but no spark at the electrode. When I bought the electrode it said it was Dometic and had a Dometic model number. I wonder if it could be a fake or something like that. When I first hooked it up I got just a small spark for a short while. Then after adjusting it some it quit sparking at all. Even just trying to hold it with insulated pliers and moving it at different distances to the metal I could not get it to spark. Of coarse with gas shut off. Here is a couple of pics the way it is right now. Having trouble posting pics. Will try again after while. Thanks

When this is all over you will be the guru of Dometic igniter operation and will help others as you travel etc... I have for years. Dirty burner and electrode contamination have been nearly 100% of the troubles.

Voltages are good! Only thing left is the igniter sending a spark and the valve opening!

So you hear it snapping but not spark?

Disconnect the electrode wire from the Igniter and test again and see/listen if you hear the snapping of an arc!
If you (EDIT) hear it then the electrode wire is shorting some where between the Igniter connection and the tip of the electrode!


Will post about how to add a pic. a bit late. I do not have the linkon this computer..jhahahaaa.

Jt

[rvman69]

It wont let me paste the pics for some reason. If I hold my finger down for the paste to come up all that comes up is select all. I know it is copied because I can paste it in my notepad. Thanks

[rvman69]

I used my Fluke meter and got 13.2v at the 12v block. Then I got 13.2v at the yellow wire going into the reignitor with the yellow wire plugged in. I could here the reignitor pulsing but no spark at the electrode. When I bought the electrode it said it was Dometic and had a Dometic model number. I wonder if it could be a fake or something like that. When I first hooked it up I got just a small spark for a short while. Then after adjusting it some it quit sparking at all. Even just trying to hold it with insulated pliers and moving it at different distances to the metal I could not get it to spark. Of coarse with gas shut off. Here is a couple of pics the way it is right now. Having trouble posting pics. Will try again after while. Thanks

[bigfootford]

rvman69 wrote:
Since I have the fridge on cant I just unplug it in the access panel and it switch to gas automatically to test the voltage at the gas valve and reignitor? I might have to do it a couple of times since it might not stay active long enough to test both. I might just test at the reignitor since I can here the gas valve turn on. I will use the ground lug where the reignitor is grounded for my test. Thanks

Yes you can do that but the voltage is only going to be there for about 3 seconds. You might need someone to help you.

Test your DVM on a dry cell battery or on the fridge 12 volt source to make sure it is reading 12 vdc. Set the DVM to 20 vdc!w

Fridge power on.

Have it on AC.

Pull the plug

You should hear the gas valve click.

Watch the voltage on the gas valve or the IGNITER if you can get on the wire.... You will see it for only 3 seconds or so.

Jim

[rvman69]

Since I have the fridge on cant I just unplug it in the access panel and it switch to gas automatically to test the voltage at the gas valve and reignitor? I might have to do it a couple of times since it might not stay active long enough to test both. I might just test at the reignitor since I can here the gas valve turn on. I will use the ground lug where the reignitor is grounded for my test. Thanks