Re: Thermal mass and ground loop heat pump question

[No Body]

On Mon, 25 Mar 2013 03:43:29 -0700 (PDT), pwate...@gmail.com
<pwate...@gmail.com> wrote:
> On Monday, January 22, 2001 10:26:06 PM UTC+5:30, Gareth Jones wrote:
>> <Posted from the alt.hvac group>
>> Hi Folks,
>> Although this is a posting from the UK, you US people seem to have a
>> load of experience in this area so please don't let a small stretch of
>> water put you off replying ;-)

As you have observed, reality sucks...

From that point of view, I'd suggest you don't "guess" about what you
need for capacity on your ground source heat pump..

For several reasons:

1) too small, and you won't have any recourse that you can afford.
2) too large and you won't get the energy savings you need to use the
cheap power.
3) There is no need to guess!

There has been a lot written about super efficient heating and cooling
systems.. and how to build building envelopes which maximize the benefits.

If you are going to go to the expense of buying US made windows, you might
as well spend some money on engineering, and get the results you expect.

Speding money on engineernig will pay off.. you can use passive solar
and get a lot of heating effiency.. Maybe so much so that you don't need
much in the way of a mechanical heating system.

You need to be cautious with super insulated buildings, especially in
damp climates. If you don't do an adiquate job of the ventilation part of
HVAC you can end up with an interiour environment that will grow all sorts
of nasty things, like molds.

You also end up with issues where building materials outgas and create an
unhealthy environment.

All that, said.. a 4000 SQ foot house with 5 bedrooms is not small. In
fact, by modern standards, it's pretty big!

Do you really need that much house? Remember, you will be paying to heat
and cool this thing for years to come.

If you are already considering a masonry house.. have you looked into
insulated concrete? A cast in place wall, using insulated forms can give
you a high R-value wall.. and a solid structure as well. It also gives you
a fast and efficient building method.

Spend some time and money on proper engineering and have a house you will
enjoy, and will "pay back" in savings over years to come.

Ground source heat pump is a good method.. provided you have the land.

Realize that you need either 1) a source of water like a pond or a
river, or 2) enough land for a "slinky" type ground loop or 3) vertical
wells with hairpin heat exchangers in them. All of these are expensive
to install.. Especially if you have "over done it". Unless your water
quality is WONDERFUL, don't use an open loop heat exchanger.. too many
hassles. Too much energy wasted in pumping. Yes, it's been done.. I
lived in a house were it was done.. but.. you need a supply and
a "dump" well.. many jurisdictions won't let you put water back
into an aquafer.. even if all you did was heat it or cool it.

Do not, do the direct burrial of a gasious refrigeration line.. too
prone to leaks. (It's been tried.. Most people regret it.)