My coleman mah 3 roof top will not blowon fan side

Sounds like you have either a bad fan motor or a bad fan motor capacitor. When you turn the unit on with the fan not working, the compressor (the humming noise) runs and gets real hot real quick resulting in the compressor cutting off ( the nothing after) on it's inside high temp switch. This is what the compressor is designed to do so that when this happens, it does not burn the compressor out. Replace you fan capacitor, give the compressor an hour to cool, then try it. In most cases and if I'm correct, the unit will run just like you want it to. Good luck.
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