Absorption Fridge Fix
Issue resolved on Norcold N611 Absorption fridge. 2015 Lance model 1995. We ride it hard and put it up wet. Been on 227 (over 22k miles) camping trips with it since 2015. Mostly boondocking in the national forests, BLMs, and remote state parks (like interior Big Bend Ranch State Park, IYKYK).
TLDR – in gas mode fridge would light, but didn’t know it was lit, so eventually would shut itself down for safety. Taking an emery cloth to the igniter and burner resolved the issue.
Long version with theory and disclaimer.
Disclaimer. If you aren’t experienced with working with propane appliances you probably shouldn’t attempt this. Proceed at your own risk. There are professionals who get paid to do this shit.
Problem: fridge would light, you know that “tick tick tick tick tick.” It would light right away, but the tick tick ticking would continue every every 5 seconds or so, indicating that it didn’t know it had lit, or thought the flame had blown out and is attempting to relight. This is a built in safety feature. If it senses no flame after so many attempts to light, it will shut off the gas and your green “on” light and orange “gas” light will flash on the front of the fridge alerting you to the issue. This prevents gas build up that could potentially cause a fire.
When the fridges senses it’s not down to proper temp, it sends a signal to the gas solenoid to open the flow of gas as well as a voltage to the electrode that sits about 3/16th inch above the burner, creating a spark. The spark ignites the gas, then the same electrode acts as a sensor by continuing to supply a small voltage measured in milliamps. The computer board monitors the milliamps. This voltage travels through the electrode and through the carbon of the flame and reaches the burner – which is grounded. No flame – no circuit for this small signal to travel to in order to reach ground. Computer board shuts off the gas flow if this happens.
In the picture, you see the blue flame. Looking exactly like it should. You see the red cable plugged into the frame, and to the right of it is the gas tube flange nutted to the burner. One Philips head screw holds each item to the frame. Removing both is as simple as removing the one screw that holds them in. Turned off the gas at the tanks. Burned the remaining gas off with the stove.
Prior to removing the burner tube, you must unthread the flange nut from the copper gas tube securing it to the burner tube. Then the tube slides right out.
Cleaned both the electrode and the burner with emery cloth (like fine sand paper). Reinstalled both. Reconnected the gas and checked for leaks with some liquid gas detector. Sealed fine. Turned the fridge back on. Fired right up as usual. Additionally, the minute it fired up, the tick ticking stoped. It now knows there’s a flame. Side note, since the part was so cheap anyways, I ordered a new igniter electrode off Amazon for about $19 and replaced the 10 year old one since I was in there anyways. Replacing that part did not fully fix the issue but when combined with cleaning the burn tube the issue was fully resolved. Also, while I was in there I went ahead and vacuumed the entire area and wiped it all down.
I was low-key hoping I wouldn’t be able to fix it. Would’ve provided me with the excuse I needed to get one of them high speed 12-volt compressor fridges. The one I was eyeballing that would be a direct-fit replacement costs about $1300. We’ve got the solar and battery power to be able to run it instead of the propane.