Make sure it does a defrost cycle every now and then. In certain conditions, the coils outside can get iced up - there is a cycle that is supposed to melt that stuff off. Good airflow is important too, so it can suck every last bit of heat out of the surrounding area.

But..once it gets that cold, it's struggles to give you heat. The heatstrips ought to come on, once the pump can't hack it. (besides when you turn up the thermostat past 2-3 degrees above current room temp). Having the heatstrips do their thing for 20 mins. might use up around the same amount of electricity as the pump running for an hour and 20 mins.

It is 39 here right now, and it heated my house up a degree (70 ->71) in about 15 mins.

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D