also, the 100,000 btu heater that you are replacing doesn't tell us anything
about your ductwork. To make sure your ductwork is adequate and the heatpump
is the correct size, you should really get a pro to do a heatload
calculation and another thing they call a manual D(I'm pretty sure that's
what it is). This involves measuring your house, including windows, doors
and ceiling height and taking note of the N/S/E/W orientation of your house
as well as the building materials. Then they enter all that info into some
magic software program and that tells them how big of a heater and ductwork
you need. Just because your old heater was 100,000 BUT's doesn't mean your
new one has to be. New ones are more efficient.