Dometic Refrig. won't run on AC

onthebus wrote:
The RM2652 is a dual fuel unit. If there is AC power it runs on that and when there is no AC it runs on propane. The DC voltage is for the controls and gas ignition. If the gas is shut off with no AC hooked to the vehicle both lights on the control panel come on indicating the unit is not running. I have a 120 AC heater (tested bad) on order and because the unit still runs on gas I believe the heater replacement will fix my problem. If not I will have to replace the board.

Thanks to all for your input

1. There is NO indication on a Dometic refer, when any part of the 120 system fails(fuse or element) other than the refer will NOT cool
2. It takes 12 volt DC power to operate the refer on 120 also.
3. If the 120 element tested bad, all you have to do is test the 2 spade terminals on the control board for 120 current. THAT will tell you if the control module is bad. No current? Check the 120 fuse on the board. Doug

The RM2652 is a dual fuel unit. If there is AC power it runs on that and when there is no AC it runs on propane. The DC voltage is for the controls and gas ignition. If the gas is shut off with no AC hooked to the vehicle both lights on the control panel come on indicating the unit is not running. I have a 120 AC heater (tested bad) on order and because the unit still runs on gas I believe the heater replacement will fix my problem. If not I will have to replace the board.

Thanks to all for your input

navegator wrote:
Some older refrigerators operated on 110 Va/c, 12 DCv and propane, those had the disadvantage that they would run the house battery down very fast, so the manufacturer decided that only 110 Va/c and propane where a better deal.

Today all are 110Va/c and propane and they can switch from one source to the other so long as the house battery is conected.

navegator

When you had a 3 way RV refer, the refer was and is not designed to COOL DOWN on 12 volt heat Element. Never was. The 12 volt Heat Element was for In Transit operation to MAINTAIN the existing cold in the refer. In the 1980's Dometic came out with the AES control system for the 3 way refers. You had an Ignition activation controlled wire to activate the 12 volt element. This Ignition wire was optional. NO Ignition wire with 12 volts, then the 12 volt element would not activate. With a Motorhome, you ran a 12 volt wire from the ignition side to the refer. With a Towable, you ran the Ignition wire from the Tow vehicle thru the CENTER post of the 7 way Bargman tow plug to the refer. 3 way refer's now, they just make YOU understand that you must have the Engine running when you engage the 12 volt heat Element. Doug

Some older refrigerators operated on 110 Va/c, 12 DCv and propane, those had the disadvantage that they would run the house battery down very fast, so the manufacturer decided that only 110 Va/c and propane where a better deal.

Today all are 110Va/c and propane and they can switch from one source to the other so long as the house battery is conected.

navegator

If the fridge is Three-Way (LPG + 120VAC + 12VDC) then it'll have a 12VDC element in addition to the 120VAC one. Three-Ways aren't all that common anymore. The 120VAC element tests across its two wire. The 12VDC element tests one wire to ground (its shell). If a 120VAC element has continuity to its shell, it's bad.

I always thought the dometic element was 12 volt DC?

Thanks to everyone for your replies to my problem. I did disconnect the heating element and plugged it in to 110 AC as suggested and fortunately it was the bad component at least I think it was better to be bad than the circuit board. The heating element is somewhat hard to take out with the sort of overlapping sheet metal that make up the chimney

Thanks much!!!!

Checking the heating element as per Old Biscuit's directions

"Best way to check it....unplug it from control board and then connect it to 110V AC power directly.
This will check that heater element works and whether problem is with element or control board. If it works wired directly...control board is bad"

Moved to Tech Issues forum from DIY.

First check that outlet fridge plugs into has AC power

If the 5A fuse on control board is good......then need to check the electric heater element.

Best way to check it....unplug it from control board and then connect it to 110V AC power directly.
This will check that heater element works and whether problem is with element or control board. If it works wired directly...control board is bad.

One more thought on the fridge not runing on A/C the heating element on the heater might be shot or the control board is going out.

navegator