Coleman-Mach 48008-966 AC large voltage drop

Skibane wrote:
It sounds like your compressor is trying to re-start too soon.

After they have shut off, most compressors need some time for the refrigerant pressure to subside on the high-pressure side of the evaporator coils.

If too much of this pressure remains when the compressor attempts to start again, it makes the compressor work much harder while starting - or may even prevent it from starting.

While it's attempting to start against too much pressure, the compressor draws an excessive amount of current. If it fails to start, it will continue drawing a lot of current for a few seconds, until the overload protector opens the circuit supplying power to it.

During those periods with it is drawing excessive current, the voltage being supplied to the RV tends to drop - which makes the lights dim and the fan slow down.

This is likely your issue (might be compounded by marginal park voltage which will result in higher amperage draws and amps are what triggers the breakers to trip.).

Newer electronic thermostats have a delay built in, once the compressor shuts off, it won't allow it to start again for a few minutes. This allows the pressure to drop allowing the compressor to start more easily.

The fan makes most of the noise but if you listen closely, you can often hear the compressor kick on in the background. The compressor is by far the bigger load.