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Mon Jan 22, 2024 3:02 am

The flame indicator doesn't do it's job. How do I find out what's wrong? I pulled the fridge out and it is on the bench and working. I pulled 12v from the aux battery and hooked up a coleman propane cannister with regulator. I'm planning to buy a couple micro computer fans to increase the heat transfer and maybe inside the box. I have to check the thermocouple on the back because there is a fan switch that never goes off.

Mon Jan 22, 2024 3:32 am

Exactly which flame indicator are you talking about?
How about a photo or two so we can see which version of fridge you have.

All of them have a flame sight glass in the lower corner inside the fridge.
Some early fridges have a flame indicator gauge built into the fridge itself.
Most years have a flame led on the sink/stove unit led panel.
When you are testing the fridge with it out of the cabinet the led panel flame led isn't expected to work without an additional ground wire during the testing.

Mark

vantane wrote: The flame indicator doesn't do it's job. How do I find out what's wrong? I pulled the fridge out and it is on the bench and working. I pulled 12v from the aux battery and hooked up a coleman propane cannister with regulator. I'm planning to buy a couple micro computer fans to increase the heat transfer and maybe inside the box. I have to check the thermocouple on the back because there is a fan switch that never goes off.

Mon Jan 22, 2024 10:31 am

I there a way to test the LED indicator on the control panel lights up on a bench test? The blue flame is so dim I have to be in total darkness to see it's glow.

Mon Jan 22, 2024 11:56 am

vantane wrote: The flame indicator doesn't do it's job. How do I find out what's wrong? I pulled the fridge out and it is on the bench and working. I pulled 12v from the aux battery and hooked up a coleman propane cannister with regulator. I'm planning to buy a couple micro computer fans to increase the heat transfer and maybe inside the box. I have to check the thermocouple on the back because there is a fan switch that never goes off.

Replace the LED lights and circuit board. I got a GoWesty replacement and it is wonderful for the power, water and fridge lights. The flame indicator is REALLY bright.

Mon Jan 22, 2024 12:16 pm

The thermocouple generates only a few 10's of millivolts. That voltage goes into an inverting amplifier and the amplifier drives the LED. Rarely do LEDs fail when only driven with 5 - 10 mA. Most likely it is the TC or the connector in between.

To test the LED, disconnect the thermocouple and make sure the indicator panel is ON. Attach a 1.5V battery with BATT+ going to the black wire and BATT- going to the white wire. You are actually applying a negative voltage to the TC input because the LED is driven with an inverting amplifier.

You must disconnect the TC because it will represent a short the the 1.5V battery. I am not sure of the best way to disconnect it but I am not suggesting you cut the wires.

Mon Jan 22, 2024 5:33 pm

What would be the effect of cleaning a thermocouple that was encrusted with Fe on the voltage I wonder. I need to get a millivolt tester.

But there is no way to test the LED flame indicator without the Dometic back in the cabinet. If I light the burner and the LED doesn't light then I need to buy the PCB because the thermocouple must be good otherwise the burner wouldn't stay lit.