I was quoted for both horizontal and vertical closed loop 3 ton systems.  I was told the vertical is done by drilling a 200 foot hole and put a U-bend pipe down it.  The horizontal would dig a 250' long 6' deep trench lay down the pipe, then 2' dirt on top of that pipe, then loop back and forth, with an additional 125' 6' trench done the same way for the 3 ton system.

1.  Is the vertical system any more efficient?  If so, is 200 deep enough to acheive this?  If not, what would be the recommeded depth for a 3 ton system.

2.  The vertical system is about $2000 more to do due to the drilling.  Would you think I could have them dig another well, since they will have all the drilling equipment on site, for a very reasonalbe cost for drinking purposes?  My other alternative is to trench in 1/4 mile to hook up to the rural water supply.  I have been quoted $2 per foot for the trench work ($2640)+2" schedule 40 piping ($1000)+ meter to hook up ($2000) for a total project of $5640.  I have also have considered doing it myself by renting a ditch witch ($260 per day, est. 1 day rental), piping ($800 at Locke Supply), meter ($2000) to the tune of $3060, saving a couple thousand in sweat equity.  Can a well be dug for the house water supply for equal to less money than tying into the rural water supply?

3.  If the cost is equal for well or rural, what is your opinion on maintanence costs?  No monthly water bill, only a slight elecric bill for pumping it.  Long term costs for how long well pumps last?

Any input would be greatly appreciated.

Chris

Not sure about 1 I will let the experts help.

With drilling or using "city" water it would depend on your water from the well. Where we used to live the water was hard, like 60 something, with lots of minerals in it. We had a $6000 water filtering and softening system and we would only drink the water if it was run through an R/O the system used about 50 lbs of salt a week. I wouldn't like to go back to that.

Having said that I think it is cheaper to water gardens and such from a well, and probably better for them then using treated city water.

So no real answer, but more to think about.

What do you mean rural water supply? Water supplied by the city? I did the calculations once to use city water, as opposed to a well and I came up with a $300 a month water bill alone, not counting electric required to run the geothermal system. If your thinking about using city water, stick with oil or natural gas, it's cheaper then tying into city water.

Techgromit,

The geothermal system will be a closed loop system, glycol charged, not using a well to pump the geothermal system.  It is rural becuase the water is supplied by Butler county and not the city of Augusta.  That's what I'm coming up too.  Just to tie in would be $3000-$6000 + monthly water bills and little fees.  To dig a well in our area is $17-$19 per foot to drill.  Our neibor said they hit water at 60 feet but went down to 100 to use as a reservoir.  We would most likely use a holding tank instead and may not have to dig too deep.  Even if it were 100 feet it would be upwards of $2000 + $500 for the pump, and probably not more than a total install of $3000.  Then only a small elecric bill to pump it.  I hope that clarifies things.

 

Chris

My cost to drill 600' (3-200' wells) was $4,200. It was a flat rate of $7/foot so I doubt you'd get much of a break on a second well. Your geothermal bores are supposed to 50' away from your domestic well so they have to tear down the rig, move it and set it back up. They might come down a little but don't count on it.

My installer wouldn't quote the horizontal due to the rock in my area. If they hit rock at your house they'll probably charge you to remove it so check your proposal.

Something else to consider- I don't know where your trench will be but if its in your yard, that's a lot of lawn repair.

I would think a well would be cheaper than connecting to city water but you have to decide if the risk of running out of water or if the risk of poor quality is too much for you to bare. It wasn't an option for me so we drilled. I've got good water and plenty of it.

If both the vertical and horizontal systems are designed using the same parameters,  neither will be more or less efficient that the other as long as both are installed correctly.

My guess is that you will have one 200' bore hole per ton,  not just one for all 3 tons.  Drilling to deeper depths would make you system slightly more efficient,  but you would probably never pay back what it cost you to drill deeper.

I second what Dewayne said on efficiency.

On the water well, I would recommend you go for the water well. If water is only 60' deep, and you only need a 100' total, go for it. I'd recommend a variable speed pump, too. They're wonderful. In fact, you can get away with smaller casing, and those variable pumps will still pump up to 40 gpm. ( with a 3" pump). Your neighbor with the water well, how hard is their water? Is it good? You'll beat out the city water's price, and not be restricted, too.

If I were drilling for a water well on the same site I drilled for a geo system, I'd give a significant discount on the water well. I wouldn't have to charge for mobilization again, and most all my stuff would already be there.

Climatemaster indicates greater efficiency in heating with open loop and closed loop for cooling. If water quality is good, I don't mind folks around here going open. Water quality definately has an impact (due to maint. costs) and never would I suggest someone use metered water (a gas bill could easily be cheaper).
joe