Roof ac compressor not starting

[Turbojack]

Originally Posted by shepardmike

I have Dometic Penguin II's and have been struggling with cooling since I owned my coach. Last month, I had a Dometic tech on the phone telling me that 3 - 5 years is all you get. Wish I had the capital to start a mini - split solution for RV company..

I have a mini-split at the office and have about the same luck. Just out of warranty and have to buy another one. At shop also have a regular old AC unit and it has been going strong since 1997. I just replaced it last year since I did not want to have it die when we were really needing it.

[cshippey]

Go to a refrigeration supply house, (R E Michael, Grainger, Baker Supply, and purchase a solid state hard start kit. Cost around $25. Install it on your unit and see if it starts. I doubt you have a refrigerant leak. These compressors frequently stick and can sometimes be started with a hard start kit. This is only a temporary fix. If it starts the unit may run for another year or another minute but the hard start kit is definitely less expensive than a unit.

[Hallen01]

Originally Posted by ChuckGirard

Was on the roof today trying to get my front ac to blow cold air. Replaced both capacitors with the mid one and still no joy.

Symptoms are the interior air starts circulating and can hear the compressor try to power on and immediately cuts out. Same happens when capacitors are exchanged. ...

If you had said that the compressor was not just trying but simply would not come on, then I would say that the startup delay module might be at fault. That circuitry (shown in the attached photo) is located in one corner of the AC, and is a high failure rate item that will prevent the AC compressor from starting if it (the startup delay module) fails. You may simply bypass it by plugging the module "in" plug to the module "out" plug (intuitive - even for me). However if you do that for more than one A/C unit, then you should turn them on one at a time, not have them all try to go on at a high startup amp draw when you plug in to 50A shore power (or start the generator).

[Rockwood27]

Watch this YouTube video. It has great diagnostic on RV ACs.

https://youtu.be/3VckFAXg1CY

Sent from my SM-A515U using iRV2 - RV Forum mobile app

[Steve 716]

The air conditioner is purpose designed with a sealed compressor. That means you cannot replace the compressor and you cannot charge the system. The only thing you can do is to replace the entire AC. My front AC compressor failed. NIRVC had a system in stock and replaced my AC to fix the problem.

[oneknight]

I had two ofine not start the compressor, in 2019.
After a bunch of circuit testing and schematic tracing, I bypassed the high pressure fault. This is a weird system with a latching relay where the slightest blip will take out the compressor until you power cycle it.

This was 4 years ago, those units work perfect to this day.

[DSL417]

Plan on a new AC unit…planned obsolescence I think…just replace my front two two months ago. They don’t run forever!