We have model #57915.54. The fan and compressor run, but is blowing hot air. Is there freon for the unit? If so, I heard that there was a kit you could purchase to do it.

charge with freon

The buzz is the compressor failing to start.The blue or purple wire from the compressor goes to herm on the capacitor. If it's wired right and does not stare the compressor is bad.

sounds like it is either low on Freon or the compressor is going out. The blowing ice cold is an indicator that it may be freezing up because the low Freon. when it stops blowing cold, turn it to fan only mode and see if it gets colder again. If that is the case then the unit is low on freon and freezing up. I know that sounds confusing but that is how AC works. The low freon pressure means the gas is expanding too fast and the air flow cannot take up the cold from the evaporator fast enough. Turning the compressor off and keeping the fan on will alow the room air to take up the cold.

Bad run capacitor or bad compressor. If you hear an occasional click from the compressor try a new run cap and then a hard start kit. Otherwise it's more economical to purchase a new unit.

If it is blowing air and the compressor is running you are low on freon more than likely. make sure the fan on the unit is also running it helps it get rid of heat on the external coils. if all fans are running and the compressor is running it is low on freon.

If the Air comeing out is the same as the temp inside the RV make sure the compressor is running and not just the fans. It could be low on freon. If freon is ok then you would need to ck the wiring to the selector switch for a short. It would be obviouse because there will be melted wires. I am leaning toword low on freon since you have already been inside the wiring/control unit.

very good possibility that it is low on freon. If indoor unit is blowing ambient air, not cooling is happening. If this is the case and you are sure the compressor is running and then shutting off, the compressor could be overheating and the internal overload is taking out the compressor. If outdoor fan runs and compressor runs, probably cause. If capacitor is bad, unit would most likely not run that long. While unit is running, feel the large line at the condensing unit. If it is cold, and stays cold, could be something else going on. If stays warm, most likely low on freon.

check the compressor temperature if hot check refrigerant charge is less.

this could be a lot of things but your outdoor unit probably isn't running if the fan outside is then the compressor isn't it is either not getting a signal from the t-stat or the unit is out of freon and the pressure switch has kept the unit off, if it is out of freon the fan nor the comp will be on, and in addition to all that it could have a bad dual run capacitor

Most likely the unit is low on refrigerant. You could also have a restriction in the system. You need to put gauges on the unit.