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Originally Posted by cbearden
I'm planning to use this unit for water-to-water, as you've described in your first machine. my plan is to hook one side into my hydronic floor and the other side into either solar panels or loops in ground. Both the solar panels and the loops in the ground I plan on building later on.
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This all sounds just great!
The solar idea is good. At some point you'll need to do a site analysis to see how much solar energy you can realistically expect during the heating season. Also you might need to decide if you want your solar to play a primary part in meeting your heating requirements and have the GSHP fill in the rest, or the other way around. Keep in mind that solar temperatures can get very high, so high that it could have a disruptive effect on your heat pump if used directly, but if the temperatures were moderated by a very large heat storage system (using the earth or a very large tank of water or massive concrete slab), you could make it work.
Quote:
Originally Posted by cbearden
...reading your previous posts on here, I was trying to use something smaller to learn/test this initially.
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Yes, that's the best way to go...
Quote:
Originally Posted by cbearden
the hydronic floor part of our house is about 1000 sq ft. it's a 2-story house, but I only have this in the first floor.
I've calculated the heat load of my entire house to be in the area of around 18000-22000 btu, with the added insulation we'll be installing.
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18000-22000 btu...
Well, let's look at the specs you posted on your de-humidifier:
Cooling Capacity - 7250 BTU/hr (2125 Watts)
Motor Input - 671 watts
COP - 3.16
Looking just at the motor input of 671 watts. and the COP of 3.16, we can do a rough calculation of what the output might be:
671 * 3.16 = 2,120.36 watts
Since 1 watt = 3.412 BTUs,
2120.36 * 3.412 = 7,235 BTU, which roughly corresponds to the output stated on the label.
The heating requirements you supplied were 18000-22000 btu
So your experimental project could supply...
(7,235/18000) * 100 = 40%
(7,235/22000) * 100 = 33%
...between 33% and 40% of your maximum heating needs.
As you can see, your experiment could not only be a learning experience, but also a very significant contribution to your heating needs. You are on the right track.
But don't make this whole thing too 'precious'. You are learning, you will make mistakes and might destroy your unit in the process (hopefully learning all the while). NOT A PROBLEM. I just wanted to do some calcs for you so that you had some idea of the potential you are working with.
Quote:
Originally Posted by cbearden
...I have a larger 230v 18000 btu unit that someone gave to me and doesn't work. I haven't dug into it as of yet...
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This could be the donor for your final heat pump.
But I think a more interesting way to go would be to build two smaller heat pumps that together would supply somewhat less than your total heat needs.
So if you could locate a 1-Ton unit, it could supply about 12,000 BTU of your needs, and a unit like the one you have could supply 7,235 BTU...
Total = (7,235 + 12,000) = 19,235 BTU
You could run them as needed, first the smaller one in the beginning of the heating season, then switch to the larger one as weather got colder, then run them both in the coldest part of the season, and finally add some axillary heat on the days when the extreme weather days were upon you.
Your micro-controller could switch the units in and out as required.
But the success of this whole scheme will depend on the accuracy of your heat load analysis.
I know that it is easy to get carried away with over-estimating the effects of future projects, so it is very important that you are realistic with your heating needs analysis, because the success of the heat pump(s) you build will be determined by by the load. And much more to the point, your earth work, the extent of your loop field which is a BIG DEAL will depend on your heating analysis.
Best,
-AC