Geothermal Loops?

[eepete]

If you have not done so, read this thread on geothermal pond loops:

http://www.tractorbynet.com/forums/projects/196751-geothermal-pond-loop.html

Pete

 

[powerstroke444e]

It was built in 1860 with remodel in 1990's but they didn't use any insulation.

This is where I'd definately put some reassurance, insulation, IMO, can make or break a house for heating and/or cooling. A person can have the biggest badest setup there is but without good insulation it won't mount to a hill of beans

Yes I have added attic insulation and planning residing and insulating walls when in 2 years when we remove wood siding and add the laundry room. Its all a 6 year plan as we are paying as we go. Its came along ways in last year since we bought it.

 

[bruceha2000]

Yes I have added attic insulation and planning residing and insulating walls when in 2 years when we remove wood siding and add the laundry room. Its all a 6 year plan as we are paying as we go. Its came along ways in last year since we bought it.

You might want to put off the geothermal until the house is properly insulated. You are either buying a lot more 'tonnage' than you need or planning on supplemental heat until you insulate. Either would be a waste of money. Insulating is the most cost efficient way to reduce HVAC energy use.

It would be cheaper to have the wall cavities filled now and pay less to heat and cool for the next 2 years. They will plug the holes in the siding which you are planning to replace in 2 years anyway. Then have an energy audit done and get the proper size Geo system. Maybe even have an audit done first, there might be other things you need to do at the same time to tighten up the house though replacing windows would probably be better done when you replace the siding unless they are single pane with pocket weights .

The cost to insulate in 2 years will probably go up (like everything) so the difference in cost (plugging the holes mostly) will be little to none, maybe even cheaper now so you would be well ahead money wise. The other option would be to wait the 2 years and take off the siding AND sheathing and fill with batts. That would be a LOT MORE work and expense (unless you do all the work yourself).

 

[powerstroke444e]

The right size with insulation and addition is six ton or a dual zone multi unit system. I agree that cost wise insulation would go along ways which is why we did the attic but the wall will have to wait.

Its just one of those 5 yrs from now it wont matter which came 1st the insulation or geo because both will be done and I hate doing things twice or having to not complete a project because of lack of funding.

Talked to a geo specialist and looked at a system with loops that were 44 inches and owner was very happy with how it was working.

 

[simoutdoors]

Problem with geothermal is there are too many "qualified" professionals pretending to "engineer" these systems using generic rules of thumb. It seems every practitioner has an angle, mostly because it is the way they make the most $$.

A well driller will sell you on the open loops because they know how to make $$ drilling wells. Another practitioner will sell you on vertical closed loops with grout because they are likely the distributor for the grout. Others sell special pipe that has magical heat transfer rates.... Most are acting as design professionals without any endorsed Professional Engineering License, good luck if there are errors or omissions in their design.

Geothermal has been around for a long time, but is a very immature industry.

 

[sawduster98]

If I did it all over again...I would have the entire house insulated with closed cell foam prior to the geothermal heat. The part of my house that I did with the foam is unbelievably tight and retains heat for a long time.

 

[Chilly807]

Problem with geothermal is there are too many "qualified" professionals pretending to "engineer" these systems using generic rules of thumb.
Geothermal has been around for a long time, but is a very immature industry.

You're right about that. We had some wildly different quotes for our system three years ago, anywhere from 3 to 5 ton systems, 3/4 to 1.5 inch pipe, and different field designs, a couple of which I'm pretty sure would not have worked well at all.

We finally went with the most experienced installer we could find, and it turned out they were among the best. Not to mention the cheapest! Even at that, there were a few piping errors inside the house, but they did get rectified before we were finished.

Incidentally, there IS software designed to calculate heat loss and geothermal requirements. The installer simply plugs in the variables the program calls for and it spits out what's needed. However, they do have to understand exactly what is being requested, and how to compensate for non-standard conditions.

Sean

 

[samhudson3]

Yep, geothermal is a big outlay up front, but with tax credits (state and federal) you'll get a huge chunk of that initial money back over a short period of
time.

We replaced a heat pump with geothermal and we figure at 4 years with the credits and reduced electric bill, it would have cost the same as a new heat pump. Now we have savings on our electric bill (we heat our water with it too) into the far future.

We did our homework and got a great contractor. The only downside it the cost of the filters, which are north of $100, but last us about 18 months.

 

[powerstroke444e]

I purchased the software to do the loop design my self from the company that I am buying the geo pump from. And it showed that at 48 inches I wouldn't need electric backup till it was 6 out and that would put my water at 30 degrees. So I changed some inputs in the program and at 5 foot I can get down to 0 and shouldn't need extra heat with 3000 foot of pipe.

I had put loops in for others but never like how they wanted it done. So this will be my 1st 100% all my design and I specified all the equipment with what I feel is good equipment. If I am wrong better to be wong at home than in someone elses yard. Should take about 10hrs to put the lines in.

 

[JimRB]

When I did my house the EMC calculated 34,000 btu heating and 31,00 btu cooling with 22F outside, 70 inside and 92 outside, 75 inside for cooling using Right -J short form. The 3 ton Climatemaster with ground slinkys has worked fine at 74 all year round. At near 100 F outside it runs a lot, at 10F it runs a fair bit but no discomfort. Both of those temps are a bit out of normal seasonal weather.

They watered the dirt as they were backfilling the slinkys. I can't remember how much dirt before they watered but I know they did.

My mean earth temp is probably 14F warmer than where you live. We do just fine without booster heat but 14F earth is a lot warmer for heating.

My folks did foam in their 1900 house back in the early 1970's. They say it made a huge difference in comfort. The installers peeled off some of the redwood siding up towards the top of each floor, drilled some holes and foamed away. Years later we removed plaster and for the most part they had done a great job. A skilled insulation company should be able to foam your existing house which will make a huge difference right now but it looks like you are on your way to geothermal right now.