Coleman Roof Air Conditioner Cleaning

[SierraJoe]

I've never really used my roof air conditioner much as we usually boondock and camping where we do, our camping spots are usually above 7000 feet. I have noticed that the air conditioner compressor cycles on and off quite a bit. I inserted a temperature probe in the vent and measured a temperature of around 49 degrees with an outside temperature of around 86 degrees.  From what I read this is around the middle range of what it should be putting out, so I didn't believe it was cycling because of low refrigerant. I decided to go up on the roof and clean the coils. I took off the cover and being careful, I used a hose and sprayed the coils thoroughly making sure to not spray the motor. I couldn't believe the dirt that came out of the coils. After that, I opened the little flip cap on the fan motor to oil the fan motor. Unfortunately, it disintegrated in my hands. I filled with oil, and then sealed back the top with a blob of silicone to prevent dirt from getting inside the motor. After putting everything back together, I went back inside to see if the cleaning would make any noticeable changes. By this time, the outside temperature was 99 degrees. Output temperature was still around 49 degrees but this time the compressor was not cycling like before. From what I have read, an RV roof air conditioner will cool the inside around 20 degrees cooler than the outside. Looks like the dirty coils were overheating the compressor motor causing it to cycle on and off often. I also have a original can of R-12 refrigerant if I need to add in the future. Good thing to have as they haven't produced them since the mid 90's and they go for around $40.00 a can on e-Bay. Pretty amazing to me the system still works well after 43 years with some neglect in between those years.