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Old 01-08-18, 01:38 PM   #2
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Originally Posted by buffalobillpatrick View Post

I think? it could support a 1/2 ton heat pump.

The emitter/collector could be the upstairs underfloor pex loops?

The climate has low RH, so reaching dew point is not likely??
Hi Bill, nice to hear from you again.

You should call around to some of your local GSHP installers and ask exactly the question you have posted. The situation varies greatly from area to area. Here in Portland, it takes a 220 fooot deep borehole to yield a Ton (12,000 BTU). Or an 80 foot trench dug 6' deep with slinkies totaling maybe 250 feet, to get a Ton.

It has very much to do with your rate of heat extraction and injection. It also has a lot to do with the 'duty

It will be very interesting for you to put a data logger on your incoming water temp, and graph it over time, say a month or two.

I predict that you will see a series of down-curves, each followed immediately by a recovery curve. And that in the long term, you will have a declining ground temp.

I'd love to see the graph.

In short, my hunch is that 1/2 T is too large. I'd go for 1/3 or 1/4 Ton. But use what you have and let us know. I am very interested!!

As to your Dew-Point question, it won't matter to the buried loop.


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Last edited by AC_Hacker; 01-08-18 at 04:19 PM..
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