I have a Lennox thermopump which, when turned on to heat: the fan turns on, the compressor does not turn on and there is no hot air generated. When turned on to A/C: again the fan turns on, the compressor does not turn on and there is no cold air generated. Any ideas?

There are many reasons that could keep your compressor from running, bad capacitor,bad compressor, low on freon, loose connection or a bad contactor. Start by telling us if you have any electrical exp. If not I'd advise you to call in a pro, for this can be very dangerous.

My husband and I opened the heat pump casing this weekend and found the following: a hot scroll compressor and a buzzing sound coming from the compressor. We turned on the heat pump to A/C, the fan turned on but a buzzing sound came from the scroll compressor. (I have a video clip of the buzzing sound if anyone is interested)