On Thursday, August 22, 2019 at 2:30:04 AM UTC-4, wrote:
On Thu, 22 Aug 2019 15:22:51 +1000, "Rod Speed"
wrote:



wrote in message
.. .
On Wed, 21 Aug 2019 19:05:44 -0500, Arthur Conan Doyle
wrote:

Ralph Mowery wrote:

For heat pumps you can say that electricity is more than 100% efficient.

The heat transfered from the outside is more than the heat produced by
electricity if used as resistance heating.

True. However, heat pumps are decidedly more expensive than conventional
furnaces to install and maintain, so that does need to be considered.

If you live in a place where heat pumps actually work, you probably
have an A/C anyway. The incremental cost for the reversing valve is
minimal.

There's more involved than just a reversing valve.


But the incremental cost on the line is minimal. Just because of the
economy of scale most small HVAC systems might be heat pump by default
and it is the special order to delete it. It is getting that way with
mini splits here now.

You're correct, of course. Just to verify it, I just looked at the cost
of the eqpt for 3 ton Goodman AC 14 Seer and 3 ton Goodman Heatpump.
Both about $2300 within a hundred bucks of each other, which is nothing
since with installation around here you'd be looking at about 3.5X
that total from the contractor for replacement, a lot more for the
whole thing, ie ducts, for a new home. Heat pumps have gotten more
efficient in recent years too. The problem is the capacity. 3 tons
is 36K BTU, which is what a tiny gas furnace would be, if they even
make them that small. Even a 5 ton system is just 60K, my gas
furnace is twice that. So, the problem becomes sizing them for
colder climates. I guess it takes geothermal to get enough output,
not sure how much even those have. I know is you don't see
heatpump systems of any kind being installed here in the NYC area,
where it's not especially cold, unless it's some
tree hugger doing it outside the norm, cost be damned.