LP Gas pressure at refrigerator

[smsinville]

I've been trying to troubleshoot why my refrigerator does not work on propane: no spark, no flame. In order to test the propane, I removed the test port plug in the propane supply line at the fridge outside panel, and connected a water column manometer. When I turn open the propane valve, the gas comes into the manometer and just gurgles right through! Should I assume this means that the gas pressure to the fridge is too high (supposed to be 11 inches on manometer)? The stove burners work fine, and the propane funace works fine.

[Old-Biscuit]

smsinville wrote:
old-biscuit ... thanks for the quick reply. I have tested the current on both ends of the gas valve and it is within spec. So, it has current, yet no gas. Would you then assume that the gas valve is defective? If it is defective would that mean no spark is being sent? Thanks.

DId you test the Burner Control Module.....?
That module supplies the Current for Spark ELectrode

[Scottiemom]

Since you're in Ohio, why not take a little side trip over to Shipshewana and see Leon at National Refrigeration. Nobody better at troubleshooting and fixing RV refrigerators than Leon. And he works much cheaper than the RV businesses.

He can tell you exactly what's happening and can fix it for you. He's a young Amish man, so you can call and leave a message. He gets to his messages usually during his lunch break. But he WILL call you back. Make an appointment and he will fix you up. We were just there a few weeks ago. Fridge working, but the ARP unit was shutting it off, which is what it does, but it was happening for longer periods of time. Turns out a sensor was bad. He replaced it for $50. $25 part/$25 labor.

Dale

[smsinville]

old-biscuit ... thanks for the quick reply. I have tested the current on both ends of the gas valve and it is within spec. So, it has current, yet no gas. Would you then assume that the gas valve is defective? If it is defective would that mean no spark is being sent? Thanks.

[Old-Biscuit]

smsinville wrote:
The model is supposedly "german": RML8555. The components of the system don't match old-biscuit's diagram. (Although I've had other RV's that essentially match that layout.) It's an unusual system. The only "test port" is actually BEFORE any other components. It appears not to have a solenoid. There is a "gas control valve". ajriding ... I'll try what you suggested tomorrow. I have confirmed that there is 12 volts coming to the system. The fridge is a 3-way, and it works well on both 110 and 12v.

YES that is a totally different control scheme
It is a Dometic 8 Series (RML8555)

Gas Valves are dual serial gas modules that use Very Low Voltage (less then 1.5V)
Each valve has a test point to measure voltage and resistance (28.5 ohms)

See pg 47

Burner Control Module provides Igntion source and flame proving signal (separate spark electrode & flame ionization probe)
Also has Test points for measuring voltage

See pg 48

Service Manual

[smsinville]

The model is supposedly "german": RML8555. The components of the system don't match old-biscuit's diagram. (Although I've had other RV's that essentially match that layout.) It's an unusual system. The only "test port" is actually BEFORE any other components. It appears not to have a solenoid. There is a "gas control valve". ajriding ... I'll try what you suggested tomorrow. I have confirmed that there is 12 volts coming to the system. The fridge is a 3-way, and it works well on both 110 and 12v.

[Old-Biscuit]

smsinville wrote:
I've been trying to troubleshoot why my refrigerator does not work on propane: no spark, no flame. In order to test the propane, I removed the test port plug in the propane supply line at the fridge outside panel, and connected a water column manometer. When I turn open the propane valve, the gas comes into the manometer and just gurgles right through! Should I assume this means that the gas pressure to the fridge is too high (supposed to be 11 inches on manometer)? The stove burners work fine, and the propane funace works fine.

You have couple of issues:
No Spark/No FLame
Circuit Board sends 12VDC to gas valve and spark electrode at same time
Gas valve TEST port is downstream of gas valve/solenoid so it must be opening if you have gas flow thru manometer.



No Spark......
Circuit board sends 12VDC from transformer to electrode when gas valve is opening.
Spark gap too narrow/too wide ---no spark (1/8" - 3/16") centered directly over burner slots
Electrode wire connection clean/tight at transformer


Manometer....tubing in 'U' shape. One end Open/other end connected to gas test port. Water in tubing.
11" WC is only 0.4 psi so it should NOT gurgle THRU

[enblethen]

Make and model of refer?
Check connections to the eye brow.
Is the refer set to auto or LP?

[sayoung]

If it's not sparking, check for 12 volts to the unit.

[ajriding]

Well, if you have no spark, then start there. No spark = no flame. No flame = no work.
Try a long grill lighter and see if you can hold a lighter flame under the thermocouple where the flame should be (the fridge should be on the gas setting and set to run). I would not think you need to hold in the button since you are lighting it yourself like this.

The propane unit has a sensor (thermocouple) that senses heat (flame) and will shut off gas flow if there is no flame/heat. The "push button in while lighting" is the over-ride for this.