I was watching the Dirty Jobs show with Mike Rowe the other day.
He was helping well drillers sink wells for a heat pump system for
something like an old folks home.
It occurred to me that I haven't heard of any for plain houses. Too
By the way he can sing.
In <rjre9n$1kpm$ email@example.com> Dean Hoffman firstname.lastname@example.org writes:
Plenty out there. "Geothermal heat pump".
Problem is much higher upfront cost than traditional
air to air for cooling, and a hefty chunk more
than for natural gas or oil for heating.
I know two people that looked into it for houses they were building.
Initial cost was the deciding factor for them. Don't know enough about
the specifics and payback time.
There is a video of Mike explaining how he got into the business using
opera to get a union card.
We put in ground loop geothermal system in the house in TN to replace
the original air-exchange heat pump. Not a well, but 7-8 ft trench with
heat transfer loop tubing at bottom and about halfway.
NG not available and didn't want the big tank. With a thermal switch to
ensure the aux electric heat didn't come on unless outside temp <20 F,
it had great performance and payback compared to the older heat pump
about 4 years.
That was retrofit so excavation costs were a fair amount more than would
have been if had done when doing the excavations for basement and septic
when the house was built.
I'm sold on concept...
Ours was Water Furnace brand/manufacturer. We were there 7-8 years
after doing it and now been back to farm 20 years. Last I knew, it was
still going strong although that's about 3 years now since we stopped in
and met the folks after the folks after the folks we sold to.
We didn't do it because the layout inside the house wasn't amenable, but
one can get much cheaper hot water during cooling season from the exit
side waste heat as an additional payback mechanism.
On Tue, 15 Sep 2020 17:13:13 -0500, Dean Hoffman
All-The-Rage here about 15 years ago -
not the well-type as much as the ground loop.
My neighbour had a system installed on 2 sides
< side and back > of his ~ 3/4 acre lot.
At that time the cost was about 20 grand but the
government rebates would kick you back about
6 grand. helping greatly with the pay-back time.
They work great 3 seasons here in Southern Ontario
but the cold months require auxilliary heat.
An old high school friend (Dave Hatherton) was one of the brains
behind "water Furnace". His family was in the well drilling business
(Hadco Well Drilling in Elmira Ontario)
He's done a LOT of business in Ontario and beyond - including a lot of
>We didn't do it because the layout inside the house wasn't amenable, but
>one can get much cheaper hot water during cooling season from the exit
>side waste heat as an additional payback mechanism.
In alt.home.repair, on Tue, 15 Sep 2020 17:13:13 -0500, Dean Hoffman
I've been to a house in Dover, Del. with geothermal heating and cooling.
Not a cheap h ouse but no mansion either. T hey seem to have removed
two new AC compressors in the process of installing the geothermal.
I didn't see how evacuated tube panels worked by looking at
pictures. It seemed like the tubes should've been connected in series
with water running through them instead of parallel like they are.
This guy gave a good explanation:
My housing development down here in south Mississippi is new, with
everything either built last year or this year. Each house has the ground
loop that you described. Down here, it almost never gets down to freezing,
so the systems seem to work pretty well.
I have other concerns/complaints about the HVAC system in my house, but the
heat pump aspect of it seems to be fine.
Good on him...I've not looked since as we've got NG on farm from a tap
off the main pipeline out in the pasture, but they built a quality product.
The local contractor who had franchise in E TN had done a lot of them
down on the lakefront with the lake as the heat sink/source; ours was
the first ground loop he had done.
That's been 30+ year ago now, incredibly it seems impossible to have
been back on the farm 20 years already...
In article email@example.com,
I would think that in Mississippi it would be the oppsite. YOu do not
need to worry too much about heating, but more so with cooling and
humidity control. So better to have the coils in the cooler earth than
in the much hotter air.
I often see and understand how the efficiency of the heat pumps go down
when it gets cold and you need auxillary heat. I have never seen any
refference as to how to get extra cooling from the normal air installed
heat pumps. I am sure the gound loop system would be much more efficent
than the air system even in hot weather.
We've done a lot on commercial buildings where I work in Virginia, none on residential.
Results have been good BUT if you don't install perfectly it's really hard to troubleshoot or fix. High quality installation is more critical here than on most systems I've run into.
Most of ours are well type systems because of space. Oh, and if you aren't careful to keep all the trash out including deburring PVC, expect to be cleaning strainers for months.
Air-exchange heat pumps are just conventional A/C units when reverse
valves for A/C.
And of course it's much less efficient to discharge the waste heat from
the A/C when ambient is 100F, just as it is harder to extract heat from
<40 F air for heating.
The geothermal source/sink is much more nearly stable and if properly
sized can handle both cycles. With ours, the aux heat controls by
default would kick on with a >3 F setpoint mismatch to provide more
rapid warmup after an overnight setback in the morning, but we included
a cutout to prevent them from kicking on unless outside <20F and never
The geothermal systems also can be set up to use waste heat on cooling
cycle as preheat for hot water that can cut that cost down noticeably in
cooling season as well. That's better in warmer climates, obviously.
My office is in a building with water source heat pumps for each area.
There is a water loop for the whole building. That loop includes a cooling tower and a boiler. Then there are 20 or so individual water source heat pumps for the office areas that exchange heat with the water loop.
This type setup is new to me but the energy savings have been larger than we expected, and reliability is high. There is no outside chiller needed at all.