Geothermal Heat Pump Project

[hazmat]

How much electricity are you using to run this unit? Glad to hear it is performing better than last winter.

 

[CATMAN]

I just found this post. Very, Very interesting and thank you for all the details. I, too, wondered why you didn't put the manifold for all the 500' sections inside the basement. Just a different approach, I guess. I learned there is more to these systems than what I see at the Seattle home shows. Thanks again.

 

[techman]

Putting the manifold in the basement has no real advantage. It would take more room, more or bigger holes in the wall, etc. If you have faith in the fused joints, then I see no reason to have the manifold indoors.

Many systems have slices or joints outside. All vertical loops have multiple field joints. Thermal fusion is used. Any mechanical joint is specifically warned against by all of the geo heat pump manufacturers, due to possible leakage. If you see a cross section of a fused joint, it looks like one solid piece. So with the right tool and proper training, as well as pressure testing prior to backfill, there is no worry.

paul

 

[techman]

How much electricity are you using to run this unit? Glad to hear it is performing better than last winter.

For the last full year I averaged $ 134/mo. This is for 2900 sq-ft, all electric, w/pool, 3 computers 24/7, 4 people, 70 deg summer and winter.

Always hard to compare, but I was paying $ 30-35 per month more before, but electric rates have gone up over the last 1 1/2 years, another person in the house and other factors. One thing for sure, despite the temp being set basically the same as before, it feels more comfortable in the winter. Warmer discharge air, shorter run time and no defrost all have improved the "feel".

paul

 

[hazmat]

For the last full year I averaged $ 134/mo. This is for 2900 sq-ft, all electric, w/pool, 3 computers 24/7, 4 people, 70 deg summer and winter.

Always hard to compare, but I was paying $ 30-35 per month more before, but electric rates have gone up over the last 1 1/2 years, another person in the house and other factors. One thing for sure, despite the temp being set basically the same as before, it feels more comfortable in the winter. Warmer discharge air, shorter run time and no defrost all have improved the "feel".

paul

Wow - I probably average $134 a month for just my electric. Add another$1,500 a year for natural gas to heat my 2400 sq ft home. We're paying around $0.14 /kWh.

Someday I'm going to build my "dream house" - you can bet that geothermal is on the list. It's amazing to me that here in New England we probably have more hybrid cars per capita than anyone (save for CA) yet our building trades seem to be behind the national average as far as energy effeciency.

I've heard that geothermal isn't popular because the real savings is in the cooling side of things plus NE's granite makes installing the loop expensive.

 

[techman]

I've heard that geothermal isn't popular because the real savings is in the cooling side of things plus NE's granite makes installing the loop expensive.

Actually heating has also been quite a savings compared to my older conventional heat pumps.

As far as granite, it is actually a great geothermal material from the heat flow and thermodynamic point of view. True putting the pipe in it could be a challenge, but it would work great when it was done.

paul

 

[IXLR8]

Here is the simple pressure test rig. The tire valve at the bottom connected with the hose to the compressor.

paul

Paul,
Thank you for taking the time to put this thread together, lots of good helpful information. I do have a quick question, what did you do to seal up the penetration where the pipes come thru your basement wall??

Thanks,

 

[Country Geek]

Timely to see this thread pop up now, since I'm getting a quote for a geo system at my house. Bookmarked for later reading.

 

[techman]

Paul,
Thank you for taking the time to put this thread together, lots of good helpful information. I do have a quick question, what did you do to seal up the penetration where the pipes come thru your basement wall??

Thanks,

I core drilled the foundation, about 3/8" bigger than the pipes. I fully filled the gap with silicon rubber.

Paul

 

[buckeyefarmer]

I sleeved pvc pipe thru the wall first, used hydraulic cement. Then ran the loop pipes inside the sleave, caulking both inside and outside. I ran all my loops inside and did my header inside, so I could control each loop individually. Also, it makes purging air easy. If you header outside, you need to use to use a large flush pump to get rid of the air, by putting the header inside, with shutoff valves, you can flush with the circulating pump.