"George" wrote in message
...
I am in PA and friends put in a Mitsubishi split system a few years ago.
My friend is a really sensible guy who is analytical and not a story
teller. They decided to go with the version that also can be used as a
heat pump mainly because it wasn't that much more and for a backup. They
also have an oil fired boiler for hydronic heat.

They used it for the only source of heat the past two winters and the
house was comfortable. We haven't been down to -25F though and I think the
lowest we see here is -10 F in February.

He also ran the numbers and they were able to heat their house for less
than using oil.

Usually when it gets very cold (say somewhat below 25 deg C) ( I am in the
south so that is very cold to me) the heat pump will turn on the resitive
heating elements if it can not keep up. It may be the heating elements
turned on, but even at that, the electric heat may be cheaper than the price
of oil in an old furnace.