Hey guys,  new to the forum.  I know these have probably been asked a zillion times and i apologise for that. My wife and I are looking at having our first home being built hopefully next month in the White Mountains region of New Hampshire. I looked into Geothermal quite a bit since i first learned of it and have wanted it ever since. Im sick of dealing with the oil companies and prices of oil will only naturally go up. Our other option is propane which i really dont want to deal with either, needless to say this past winter, propane prices in the area hasnt been much less than oil.

Anyway, a lot of info i have found seems to be pretty old and it seems all the contractors we've spoken to about the house has kinda looked the other way when i brought up Geothermal. Because of cost and the returns not worth the cost. Also because our lot is pretty small(0.4ac) and the neighbour on the right is really close, they say the value of the new house with geothermal will exceed the street value of the house for those reasons. Which may well be true?
But that doesnt bother me either. We love the location and i doubt we will be selling within the next 5+ years.

The system we are considering is using our existing water well. Not sure what thats called?  There is a house on the lot now that is gonna be torn down because it is in REALLY bad shape. The well that is there now has a good flow but i have heard its only 50-75ft deep.  Thing is the water is also REALLY bad. Its  hard, got tons of sulphur and iron among other things. So maybe it would be better to drill deeper, hope it better and then use that for the geothermal too. However, the neighbours well is 630ft deep and the water still has a lot of sulphur and iron but is soft.

So question number 1: Does this sort of system require a certain flow rate that determines the well depth?

Q2: Is there anyone in the Northeast or similar climate that has had a system installed within the last 5 years that can give me a comparison of heating costs from their previous oil/kerosene/propane cost? I know this is a tough one becuase prices have changed so much in the last 5 years. The house will be around 1500sqft with 3 bedrooms and 2 & a half baths.

Which brings me to Q3: With the house being around 1500sqft and 3 beds and 2 and a half baths, is it possible to determine what size heat pump i will need?

And lastly i have learned that the right heat pump is really important. So what heat pump do you recommend as far as reliability, efficiency and warranty goes?

Thanks in advance.

Posted By Slug71 on 07 Jun 2010 10:07 PM

So question number 1: Does this sort of system require a certain flow rate that determines the well depth?
I'll yield to my well drilling colleagues, but depth and flow appear to be two different issues (iow a shallow well could offer more flow than a deep well depending on X,Y & Z).
Q2: Is there anyone in the Northeast or similar climate that has had a system installed within the last 5 years that can give me a comparison of heating costs from their previous oil/kerosene/propane cost? I know this is a tough one becuase prices have changed so much in the last 5 years. The house will be around 1500sqft with 3 bedrooms and 2 & a half baths.
Only way we can predict/compare is with accurate heat load calculations, price/kwh of electricy and other usage info.

Which brings me to Q3: With the house being around 1500sqft and 3 beds and 2 and a half baths, is it possible to determine what size heat pump i will need?
Same as above.......
And lastly i have learned that the right heat pump is really important. So what heat pump do you recommend as far as reliability, efficiency and warranty goes?
Not sure you picked that up here. The best brand of heat pump is the one sold by your area's best installer.I think most of the pros here have gone out of their way to downplay brand and emphasize installer.

Thanks in advance.

good luck,
Joe

Given the size of your lot, geo for you should only be done by someone with a boat load of experiance and a pile of good referances.  No room for a "do over".  Given the depth of your well compared to your neihbors is a twist.  Unless your shallow well has a capacity somewhere around at least 20-25 gallons a minute it is not a good candidate for a "pump and dump".  If it does have the capacity the next thing to consider is the dump.  Where are you going to put that water?  Local regulations come into play here.  If you wind up drilling a new well to your neihbors depth, a standing column system may fit the bill.  One last thing to look at is the possibility of doing a dx system inside the new buildings foot print.
  All of these options will prolly come at a premium price due to the constraints of your lot size.  You may never see any ROI.  If you were my customer I would start with my standard speach.  Geothermal is not for everyone, but if you are commited we can move forward with planning untill budget won't work, or well won't go, or regulations can not be met.
hope this helps

Slug71, have you considered a closed vertical loop system? I don't know if this would work well in your area? If feasible, it would eliminate the water flow from the ground issue and the water quality issue (if you put good water into the loop).

1) Flow rate is independent of well depth I beleve. You will need at a minimum of 4 gal/min depending on the size of the GHP (larger units require higher flows). P.S. Good water quality is VERY important. Best to put in a new well with variable speed pump and water conditioning equipment (since your building new).
2) I heated my previous house with propane (80% effiecent forced air furnace) and the cost was around $275/mo (yr round budget) for a total of over $3000 a year (granted that also included a propane hot water heater) but still outragous (and the home was very well insulated). I currently have a 2.5 ton GHP (open loop...pump and dump) for my 2500+ sq. ft. home that costs a fraction of the previous home (I'd estimate the cost to be about 1/4th or less than $800/yr).
3)For that size home I'd estimate you would need a 2.5 - 3 ton unit (provided the home is very well insulated). However, you should have a heat load calc down to be sure. P.S. I live in SW lower MI.

Posted By rjdalga on 08 Jun 2010 09:17 AM
... and water conditioning equipment...

I can see water conditioning for domestic water use.  Would water conditioning for pump and dump require expensive equipment since the geothermal system requires high water flow (with near constant flow when outdoor temperatures are extreme) and consequently have high upkeep costs?

Geome,
OPPS, Yes it would. Probably better to install whole house filter in front of GHP and condition domestic water.

Slug71, opinions vary about recouping geothermal installation cost upon sale of the house. I believe this was discussed previously here and you may be able to find it in a search. In my opinion, the system would need to save enough money (compared to other fuel options) to offset the increased mortgage (due to a higher selling price). Even then, it would take an informed buyer to recognize this. I suggest that electric bills be saved to document possibly lower electric costs.

I'm not sure that I would install geothermal in a house that I didn't PLAN to stay in long enough to recoup the savings since payback is not guaranteed at the time of sale. Of course, emergencies, change of employment, hitting the lottery, etc., may cause one to move sooner than anticipated.

Posted By rjdalga on 08 Jun 2010 12:00 PM
Probably better to install whole house filter in front
of GHP and condition domestic water.

A filter will only remove suspended solids, it will NOT remove
dissolved troublemakers such as hardness, sulfur, or iron.

Trying to improve water quality in an open loop system is very
likely to be a losing proposition. The volume of water flowing
through the heat pump is simply too large to treat economically.

Even if it's just suspended solids, typical "whole house" filters
aren't designed/intended for such large volumes.

If water quality and quantity are not absolutely reliable,
closed loop is the only way to go.

In general, the deeper you need to go for water the worse the water quality. This is due to the fact that the water has simply passed through more strata and in the process has dissolved more minerals along the way. You will need to examine the water quality, water depth (pumping costs), and well yield to evaluate open loop, standing column well, or closed loop options. -Adam

Posted By rjdalga on 08 Jun 2010 12:00 PM
Geome,
OPPS, Yes it would. Probably better to install whole house filter in front of GHP and condition domestic water.

In your neck of the woods we would install a coarse sediment filter and maybe a 2 ton or less for a 1500sf home.
J

Thanks for all the response guys, really appreciate it. It certainly is no quick decision/conclusion. For what its worth, the lot is 70ft wide and a 179ft deep. As is always, everything will come down to cost but we are considering a scratch coat of foam insulation on the exterior walls and roof and filling in the rest of the stud and ceiling with cellulose or batts.
Given the size of the lot and probably our budget, i dont think we will have many options but i'll start calling some of the guys around here that do it and get some information about them and see what they have to say.

2-3 ton system is a bet, more likely a 2 ton for a new and well insulated house.

I would forget about the pump and dump given your water issues, a vertical loopfield for a 2 ton would only require 1 borehole of 300 ft with 600 feet of 0.75 pipe in it (that would be in western new york, I don't know the soil/rock conditions in your area). No headaches, little pumping power (a one pump flowcenter would be enough).... I don't see it much more expensive then drilling a new open well, casing it, paying more for the heatpump because it now needs a NI-CU coil, paying a lot more for the stainless steel well pump, paying more for pumping power....

We use different manufactures depending on the application, the brand is the least important thing. What is important is the guy (or girl) who designs the system most efficient for you, makes a reasonable profit for his efforts, and leaves you with a never ending smile on your face....

+1 docjenser
All good advice

Given the size of your home make sure you have folks do a man. J load on the house and op cost comparisons. If your load is as low as I think it might be, savings with geo may not justify expense.
You'll want to compare to AS heat pumps and propane furnaces.

I basically also agree with docjenser with 2-caveats. First, I would use 1in ∅ HDPE (min. for a 300ft borehole) to 1-1/2in ∅ HDPE for a 1-borehole system (1-1/4in min. for a 450ft 3-ton borehole). Second, I would install a 3-ton GSHP w/2-speed compressor & variable speed air-handler.

3-parallel 150ft boreholes w/3/4in HDPE would be even better but for simplicity’s sake 1-deep borehole will also work. DX may also be a possibility w/~1/3less drilling.

SR

I am new here myself and wondering about the well issue. I have a potable well that has not been used in decades. It appears shallow as the pump is surface mounted. would a DX system into the well offer better performance than into just earth?

Re: Volleyball


A well such as you describe may not be suitable for DX. The vertical copper line set MUST have constant contact with the water or ground for its full vertical length of 100ft & 1-borehole (well if you prefer) per ton. Consult an experienced DX professional in your area to discuss what may be possible in your situation.

You may also be able to use your well in an open loop configuration, however closed loop would be the preferred method in my opinion.

SR

Just what I would have said. DX has more bores/ton than water source (albeit shorter). Neither will likely find existing shallow well adequate for closed vertical loop system.
If you have enough QUALITY gal/minute out of that well, and a place to discharge it, open loop is not a bad idea- DX or water source.
J

I had 1 pro who wants to do open loop but I really don't have a discharge place. I am on a hill and have neighbors below me. When it rains, they get my runoff and the runoff of those up the hill from me. But that is nature not my doing.
Why does the entire bore hole need to be in water? I assume most holes have ground contact initially before they hit water. My home must be over the top of the water and it is solid, no crack in foundation since the initial ones decades ago. When I say shallow, my house is probably less than 100' above the Hudson River which is still tidal. So I'm guessing tens of thousands gallons of well capacity.
Trouble right now is getting a well driller here to help me estimate what I am sitting on