The bedroom AC in my 415RW isn't cooling. It's a non-ducted unit directly above the bed. When I turn it on the fan blows and I can hear the compressor kick on and stay on, but there's no change in the air temperature. My first thought is it's low on refrigerant, but of course there's no fitting to add any. Also, if it's so low on refrigerant that there's no change in air temperature, I would expect there to be a low pressure switch that prevents the compressor from coming on. At least that's the way it works in a car or house system. Any thoughts or suggestions before I replace the entire unit? Is there something unique to these units that I don't know about?
wdk450
Well-known member
I looked at the schematic for the Dometic Penguin AC in the Forum Library ("manuals" under the "Tools" tab) here:
http://manuals.heartlandowners.org/...ic/Dometic PenguinLowProAirCondUsersGuide.pdf Page 10.
This looks like the standard Dometic wiring, with NO LOW REFRIGERANT CUTOFF SWITCH. There IS and overtemperature switch located on the top of the compressor, and maybe if the AC is run long enough with no refrigerant, this would trip. Could there be airflow leaks between the return and cooled air ducting? Have you checked the tubes temperatures going in/out of the evaporator and condenser on the roof with the unit going? Be careful of very hot tubes.
The warranty seems to be only 2 years, so you may be out of luck. It STILL may be worth your time to call Norcold. Somewhere I recall a recent story of RV air conditioners having refrigeration components that were manufactured with defects by the component sub contractor.
http://manuals.heartlandowners.org/...ic/Dometic PenguinLowProAirCondUsersGuide.pdf Page 10.
This looks like the standard Dometic wiring, with NO LOW REFRIGERANT CUTOFF SWITCH. There IS and overtemperature switch located on the top of the compressor, and maybe if the AC is run long enough with no refrigerant, this would trip. Could there be airflow leaks between the return and cooled air ducting? Have you checked the tubes temperatures going in/out of the evaporator and condenser on the roof with the unit going? Be careful of very hot tubes.
The warranty seems to be only 2 years, so you may be out of luck. It STILL may be worth your time to call Norcold. Somewhere I recall a recent story of RV air conditioners having refrigeration components that were manufactured with defects by the component sub contractor.
Thanks. I'm surprised there's no low pressure cutoff. Thought that was pretty standard on AC units. I'll have the climb up there tomorrow and see what I can figure out.
wdk450
Well-known member
BTW, there IS a low temperature ice sensor attached to the evaporator to turn off the compressor if the evaporator gets TOO COLD, and the condensate that forms on the evaporator fins might freeze up and make an ice blockage to airflow. This is run through a relay in the control board, so it doesn't show up on the top unit schematic. You said that your compressor was running anyways. Are you absolutely sure of this by vibration or current draw readings?
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I can hear the compressor come on and stay on. I haven't checked the current draw yet.
As i suspected, the fan and the compressor are running, but the condenser isn't getting warm/hot, and the evaporator isn't getting cold. The compressor gets a little warm, but that's about it. I have to assume all the refrigerant has leaked out.
