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

[bigfootford]

Great to complete this thread with a great resolution.
Sadly some folks do not complete threads like this.

Thank you sir,

Jim.

[rvman69]

Just thought I would update here that the Reignitor that I used worked great the couple of times the power went out at the campground. I brought the camper home today and the reignitor worked great all the way home. Just to let anyone that might think about doing this know it is a fix.

[bigfootford]

Wonderful, you got the dang thing fixed and now you know how simple that system works!
Congrats!!!

Jim.

[rvman69]

I finally got the new reignitor installed this past weekend. I had to install it at a little of an angle. I did not have as much room as in the video. I think this was because of the new pipes that were reworked on my Amish rebuilt cooling unit. It works great. Once I got it installed I turned the gas valve at fridge back on. Then I unplugged the fridge and it fired right up on the first spark. Then I plugged the fridge back in. I waited about 10 minutes and tested it again. It fired right up on first spark. I only had to change the end on the electrode wire. The factory negative and 12v plugged right into pins on new unit. Mine did not come with the big black boot like the one in the video. Mine just had a small little boot. So I used the boot off of the number 5 coil I replaced on my motorhome and it worked great. So my original reignitor was bad.

[bigfootford]

rvman69 wrote:
It is more expensive than the original reignitor but if the original one was still available I bet the price would not be what you find of places that did have them but are out of stock. I made sure I bought an original Atwood part and not a knock off made just like it.
Here are links to video and part.

Video
https://youtu.be/CHRTDWqUYTI?si=-frbrjvfqJ98aDsx

Part
https://www.amazon.com/gp/product/B01LRJ4TPO?ref=ppx_pt2_tab_b_prod_image

Great!
Here is the linkieeessss.

https://youtu.be/CHRTDWqUYTI?si=-frbrjvfqJ98aDsx

https://www.amazon.com/gp/product/B01LRJ4TPO?ref=ppx_pt2_tab_b_prod_image

Jim.

[rvman69]

It is more expensive than the original reignitor but if the original one was still available I bet the price would not be what you find of places that did have them but are out of stock. I made sure I bought an original Atwood part and not a knock off made just like it.
Here are links to video and part.

Video
https://youtu.be/CHRTDWqUYTI?si=-frbrjvfqJ98aDsx

Part
https://www.amazon.com/gp/product/B01LRJ4TPO?ref=ppx_pt2_tab_b_prod_image

[bigfootford]

Excellent find Ken.
Put a link to the video and the part when you get a chance.

Jim.

[rvman69]

Well the parts guy got back with me and said he had the part. I meet him and guess what he had. He had a Electrode. He said you said you needed an ignitor. I said no I said I needed a reignitor not a spark electrode. What I dont understand is I even gave him the part number off of my original reignitor. Another thing is it took him a month to get a electrode? I got one from Amazon in two days. I figured out the way my main control board and reignitor work. Once the main control board gets the call for cooling it sends 12v through the wire to the gas valve which opens up. From that same wire it takes 12v up to the reignitor. The reignitor sends high voltage to the Electrode which sparks to ground of gas burner and lights flame. The electrode also senses a small difference in resistance once the flame is lite and that shuts the reignitor off so it will no longer spark. The thermocouple is there to sense there is no longer a flame when the main control board is still thinking it needs cooling. Like the flame blows out. Then the main control board shuts everything down and starts the process all over again. Also if the main control board does not get a signal from the thermocouple saying the flame is lite in a certain amount of time it shuts everything down for a preset amount of time and then tries again. I found an Atwood 91504 Universal Ignition Control for a hot water heater that is made to do the exact same thing. It operates the same way with the electrode. You use the factory type Electrode. I will have to change some connectors. Maybe only one. I seen a video of a guy using this unit on a refrigerator setup just like mine because he could not find one and it worked just like the original. It will spark and once the flame lights it stops sparking right away. The Atwood water heater works the same way with a main board a reignitor and a thermocouple. I posted this thinking maybe someone down the line will see it and dont have to go through everything I did. I have not installed it yet but hope to this weekend. I will report back after I get it installed. It worked good for the guy in the video. It does not mount exactly the same but not a big deal. If I would have known I would have to go through all of this I don't know if I would have changed the cooling unit or just bought a new fridge. I bet saving the kind of money I did would have won out. Thanks

[rvman69]

I have a local repair guy that says he has had a reignitor ordered for 3 weeks. I am thinking the company he ordered it from does not have it. He said it was under $50. I am going to call him again tomorrow. Thanks

[bigfootford]

What happened? Fixed?

[dougrainer]

rvman69 wrote:
Doug, how does the board shut off the 12v to the reignitor and not the gas valve after the thermocouple senses flame. The same yellow wire feeds both 12v. Is this done on the board somehow? Thanks

Good question. Are you saying that the 12 volts on the yellow wire NEVER goes dead? I have never in 44 years had to check that voltage when diagnosing this type problem. Since the Yellow wire comes from the main control board, then the main control board controls the yellow wire. The spark electrode "may" also sense the flame and this tells the reignitor to stop sparking. NEVER had that come up. BUT the Thermocoupler DOES kill the power to the yellow wire IF there is no flame sensed. What I would do is connect my multi meter pos lead on the yellow at the reignitor and manually light the flame with a hand held lighter when asking for ignition. SEE if the reignitor still has 12 volt power(It should) or the gas valve would close. Doug

IGNITER
First verify proper voltage at the positive (+) and ground (-) terminals of
the ignitor. The reading should be within one volt of incoming voltage at
the main terminal block during trial-for-ianition
Next, remove high voltage cable from igniter. The igniter should produce a sparking sound, during trial-for-ianition. If not, replace the
igniter.
The igniter installed on the refrigerators as original equipment is part
number 2931132019 (RV Gas Model 679). This igniter is rated 50 MA.
This igniter may also be used on any other model.
DO NOT install the Channel Mark 6, Model 12E igniter (shown below) as a service replacement part.

[rvman69]

Doug, how does the board shut off the 12v to the reignitor and not the gas valve after the thermocouple senses flame. The same yellow wire feeds both 12v. Is this done on the board somehow? Thanks

[dougrainer]

rvman69 wrote:
Doug, let me ask this. How does the board remove the voltage from the reignitor but not the gas valve? Is there another wire that ends up feeding the gas valve 12v? Because the yellow wire that comes out of the board with the 12v goes to the gas valve then another yellow wire comes out of that same gas valve connector up to the reignitor. I am just trying to understand how it works. Thanks

The gas valve stays OPEN during that 3 attempt to start cycle. Once the 3 attempts are made and the Thermocoupler senses NO FLAME, the control board kills 12 volt power to the Reignitor and the Gas Valve at the same time. That is why, you sometimes hear a loud POP when the LP lighting sequence is happening. The LP accumulates and if you have a weak spark and does NOT light the first or second time, there is enough LP to POP when the 3rd time happens. Some model Dometics and ALL Norcolds, use the combo Spark electrode as the Spark AND the flame sensor. Doug

Now, some models, when no flame detected, stopped the valve and power to the reignitor. Then after a few seconds, started the 2nd and then the 3rd attempt. All controlled by the main control board.

[rvman69]

Doug, let me ask this. How does the board remove the voltage from the reignitor but not the gas valve? Is there another wire that ends up feeding the gas valve 12v? Because the yellow wire that comes out of the board with the 12v goes to the gas valve then another yellow wire comes out of that same gas valve connector up to the reignitor. I am just trying to understand how it works. Thanks