more heat pump questions

[pdq]

numbered wrote:
The new heat pumps are better and can work in most moderate parts of the country. Below 10 degree F temps may be a problem, and would require resistive heating (available in most models)…

^this.

Resistive electrical heat is expensive and less efficient (like only ~100% efficient, instead of the 250% efficient in normal heat pump operation), but it’s only for a couple of days.