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joe blow

ca

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Posted: 09/17/20 08:58pm Link  |  Quote  |  Print  |  Notify Moderator

Hi guys,

My refrigerator woes I cannot shake LOL. Quick synopsis:

Swapped out complete coil unit from arctic cold 4 years ago and added auxiliary fans to the condenser (3). To date the fridge cools fantastic on 110v using the heat stick. Recently the fridge starting having issues when on propane.

I called Dinosaur electronics to see if they could diagnose their board as being the issue. The tech had me do some tests and he advised to remove the gas valve, cycle it with 12v (magnet) and spray brake kleen incase their was cr*p in there and it was sticking. I did and it worked ok for a bit, but it stopped working all together that same day, one day into the trip

Fast forward to a complete new valve/burner/ignitor assembly installed today. Bled the line, fired up perfect and burned for about an hour and went out again. The fridge cycles through its on/off process and the burner comes on for 30 seconds and off for 30 seconds.....repeating.


SO....with that said.

Am I not understanding how this unit operates and it is fine or should the unit (like a water heater) stay lit until up to temp and cycle as needed? The fridge was hot when this test and valve replacement was done.

At this point I am thinking possibly the thermal switch with the two red wires on the flue or the board is the issue again.

I am kind of at a loss on this one....or I am just not understanding the propane operation.


Can someone offer some advice please.

Thanks
Joe

* This post was edited 09/17/20 09:14pm by joe blow *

Old-Biscuit

Verde Valley

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Posted: 09/17/20 10:36pm Link  |  Quote  |  Print  |  Notify Moderator

Thermal switch on stack TRIPS from overheating...NO Auto Reset
When tripped ALL DC is secured



Your model uses a spark electrode to provide ignition of gas AND a thermocouple to prove flame is lit
Bad thermocouple, bad connections etc...no flame signal so circuit board dumps DC to gas valve

Gas Valve solenoid resistance
Remove the connectors from the solenoid and measure the resistance across the terminals.
The proper reading would be 49 ohms with tolerance range of ten percent.

Thermocouple millivolt readings
To check the flame sense circuit of the lower circuit board, operate the refrigerator on GAS mode, then measure the millivolts between J3 terminal and the other wire connection from the thermocouple.
The millivolt meter should read between 25 to 35 millivolts with the gas flame burning.
Any reading below 18 millivolts could cause erratic gas operation.

Thermocouple
Dometic 2932052018
Lowest price I have seen

Service Manual


Is it time for your medication or mine?


2007 DODGE 3500 QC SRW 5.9L CTD In-Bed 'quiet gen'
2007 HitchHiker II 32.5 UKTG 2000W Xantex Inverter
On the Road Debt Free April '07
Off the road still Debt Free Jan. '14

joe blow

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Posted: 09/17/20 11:14pm Link  |  Quote  |  Print  |  Notify Moderator

Thanks old biscuit.

I saw that on line but where in the hell is this thing????

I looked everywhere and see no traces of any wires or thermocouple. The only wires I see toward the heat source are two red into a small dime sized thermal switch on the exterior of the flue. According to the illustrations you provided, it is on the assembly I replaced. There is no such thing on my assembly.

Perhaps I am missing something?

Thank you

* This post was edited 09/17/20 11:21pm by joe blow *

dougrainer

Carrolton, Texas

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Posted: 09/18/20 07:07am Link  |  Quote  |  Print  |  Notify Moderator

1. Jump the red wires to bypass the Thermal switch. That will tell you if it is a possible problem.
2. IF the LP fails to stay lit when called for, you WILL get a CHECK light.
3. If the refer is at or close to set interior temp, then leave the interior door open for 30 minutes to raise the Refer temp to continue testing.
4. YOU NEVER TAKE A GAS SOLENOID APART OR TAMPER WITH IT. PERIOD. TAKE IT LOOSE AND CHECK FOR OBSTRUCTION, BUT IF DEFECTIVE YOU REPLACE. NEVER ATTEMPT TO FIX or MODIFY. Dinosaur has some idiots working for them I guess. The Liability to tell someone to do what they did is tremendous.
5. Yes the refer LP cycles on and off as temp requirements are needed. Doug

joe blow

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Posted: 09/18/20 08:02am Link  |  Quote  |  Print  |  Notify Moderator

Thanks for the advice. I will test it in a bit once I make it outside. The dinosaur rep did not tell me to take it apart, but merely CLEAN it by cycling the magnet and blowing through it.

I never start the fridge up initially using propane. The 110v heat stick is used to bring up to temp and the gas for travel and once I am at my destination if dry camping. With that said I am not 100% familiar with the burner operation cycles, and may be chasing my tail for nothing.

Hypothetically speaking: At initial startup (hot) using the LP function only, shouldn't the flame remain on for hours straight until the fridge is up to temp.....then cycle off as need?

This is my primary question. [emoticon]

Thanks for the time
Joe





dougrainer wrote:

1. Jump the red wires to bypass the Thermal switch. That will tell you if it is a possible problem.
2. IF the LP fails to stay lit when called for, you WILL get a CHECK light.
3. If the refer is at or close to set interior temp, then leave the interior door open for 30 minutes to raise the Refer temp to continue testing.
4. YOU NEVER TAKE A GAS SOLENOID APART OR TAMPER WITH IT. PERIOD. TAKE IT LOOSE AND CHECK FOR OBSTRUCTION, BUT IF DEFECTIVE YOU REPLACE. NEVER ATTEMPT TO FIX or MODIFY. Dinosaur has some idiots working for them I guess. The Liability to tell someone to do what they did is tremendous.
5. Yes the refer LP cycles on and off as temp requirements are needed. Doug


Old-Biscuit

Verde Valley

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Posted: 09/18/20 10:33am Link  |  Quote  |  Print  |  Notify Moderator

This is the burner ASSEMBLY (burner tube with spark electrode and mounting bracket)
LARGE Hole in mounting bracket is where the Thermocouple is installed
[image]

Spark Electrode Wire plugs into end of electrode and goes to 'reigniter box' (s/b grey wire)

Thermocouple has 2 wires ----Black & Grey
Black...ground ---goes to J10 terminal on circuit board (far right side)
Grey ---DC millivolt ----goes to J3 terminal on circuit board (left side)

Your fridge was part of the RECALL....stack temp switch installed and 2 red wires (DC In/DC Out)
DC+ from terminal block to stack temp switch then back to circuit board J4 terminal. Switch Opens no DC to fridge (no functions, no lights, no display ---nothing)

dougrainer

Carrolton, Texas

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Posted: 09/18/20 01:50pm Link  |  Quote  |  Print  |  Notify Moderator

joe blow wrote:

Thanks for the advice. I will test it in a bit once I make it outside. The dinosaur rep did not tell me to take it apart, but merely CLEAN it by cycling the magnet and blowing through it.

I never start the fridge up initially using propane. The 110v heat stick is used to bring up to temp and the gas for travel and once I am at my destination if dry camping. With that said I am not 100% familiar with the burner operation cycles, and may be chasing my tail for nothing.

Hypothetically speaking: At initial startup (hot) using the LP function only, shouldn't the flame remain on for hours straight until the fridge is up to temp.....then cycle off as need?

This is my primary question. [emoticon]

Thanks for the time
Joe





dougrainer wrote:

1. Jump the red wires to bypass the Thermal switch. That will tell you if it is a possible problem.
2. IF the LP fails to stay lit when called for, you WILL get a CHECK light.
3. If the refer is at or close to set interior temp, then leave the interior door open for 30 minutes to raise the Refer temp to continue testing.
4. YOU NEVER TAKE A GAS SOLENOID APART OR TAMPER WITH IT. PERIOD. TAKE IT LOOSE AND CHECK FOR OBSTRUCTION, BUT IF DEFECTIVE YOU REPLACE. NEVER ATTEMPT TO FIX or MODIFY. Dinosaur has some idiots working for them I guess. The Liability to tell someone to do what they did is tremendous.
5. Yes the refer LP cycles on and off as temp requirements are needed. Doug


Yes, BUT, a lot of times after refer is ON 120 and temp has been reached, when you switch to LP, there is NO flame or LP operation because the Refer has reached its set temp. Confuses a lot of RV'ers. Doug

joe blow

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Posted: 09/18/20 11:10pm Link  |  Quote  |  Print  |  Notify Moderator

So after a full day of research and talking to a great tech guy at Dinosaur Electronics, this is what I came up with.

My RM3862 has what they call a "smart" eyebrow controller. After diagnosing the problem throughout the day and several phone calls with the tech, it sounds like my eyebrow controller is the issue. I installed an updated snip and clip type temp controller in the fridge a few years ago and it has worked great....initially that was suspected. Currently I have the board "jumped" with two leads I made to mimic the control of the dumb controller (simple push button on/off) and so far the burner has remained on for hours and I will report in the AM once it has been burning for 24hrs....which would be the longest it has worked on LPG since the issue reared it's head.

Thanks for the help and I will report findings

Joe

joe blow

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Posted: 09/19/20 11:21am Link  |  Quote  |  Print  |  Notify Moderator

Temp this morning -1* freezer and 27* fridge. I am going with the eyebrow being bad and needing rebuilding or replacement.

I have looked and cannot find a replacement for my style.

I wonder if I can convert to the newer style without the LAC and CLC buttons on the right which are unnecessary anyway in my climate.

joe blow

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Posted: 09/23/20 08:59pm Link  |  Quote  |  Print  |  Notify Moderator

My fridge is a 3 way (110v/12v/LPG) and considering I never use the 12 v option or the worthless LAC CLC buttons for my climate, I am able to convert my fridge to a standard two way fridge (AC/LPG) with a 35.00 board. The great people at Dinosaur electronics did the research and advised me of the ability and comparable parts, and even gave me the part number(s) that are compatible.

MY board is irrelevant and nowhere to be found....anywhere!

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