Not living in your region I cannot say for sure how accurate this price is. However, it does appear to be EXTREMELY low for a 6-ton installation including ductwork, even with you digging the trenches.

The model quoted seems to be a vertical unit not horizontal.

Who is responsible for designing the ground loop? What is the design configuration (pipe diameter, feet per ton, linear or slinky, reverse return, parallel or series etc.); for what design temperatures? No mention of antifreeze, flushing & purging. Will the headers be mounted inside the foundation or buried in the ground? Who pays the electrical hookup of the heat pump and backup? Is your electrical panel large enough? How many CFM is the duct system designed for? Are register covers included; what level of quality? Which make & model T-stat? What are Air Devices? Which high efficiency air filter system?

Has a Manual J & Manual D been performed? What credentials and experience does this installer have?

A few questions; just wondering...

SR

Here is a link that might be useful: IGSHPA

I had called a Geothermal guy yesterday for my new construction 2400 sq ft house in New Jersey. I don't have the detailed quote yet but he said it will be a 3 or 3.5 ton system. Cost $42K.

He also mentioned that in NJ, he does not recommend horizontal loop because even if it is 8ft deep - on very cold days, system does not perform well.

AJ

6 tons for 2400sqft?

"6 tons for 2400sqft?"

That would seem about right for a house with NO insulation if you like to have windows open no matter what the weather.

The installer for this is the only one in my area that does GeoThermal, but has multiple installations of these units. I also thought that 6 tons might be overkill, but he stated that he would have a Load Capacity(?) for me next week.

Thanks for the questions that you gave so that I can ask the Installer.

Your insulation level is low. Put more money into achieving higher R values. Foam sheathing for the exterior and thicker cellulose in the attic plus a radiant barrier.

Then, get an estimate for a 15/16 SEER heat pump system. At 7cents/kwh, your power is cheap. It might be that at those rates it might take 30 years to make up the price difference between a higher-efficiency air-source heat pump and geothermal.

Well, I have gotten a quote for a 14 SEER unit from the same Installer. here is the details:

Installation of a Goodman 14 SEER 5 ton heat pump (SSZ140601) , with a Goodman Trane 4/5 ton electric air handler (ARUF496116) with 20 KW electric heat.

Price also includes complete metal insulated duct system, supply vents in all rooms and returns in each bedroom and main living area, and installation same as above.

Price is $8,950, and my Elec Coop has a rebate program of $250 per ton ($1,250), which makes total price around $7,700.

Thoughts???

Your geo is so cheap that it is probably worth it even at your crazy cheap electric rates. I don't really know the climate in OK but in central NC, at your rates, you are looking at $500 a year for conventional ASHP and $350 a year for geothermal, so your payback is close to 30 years.

That is assuming you use enough electricity from other things to get to the lower rates for most of your heat. And it is assuming that the house is built fairly tight. Your insulation levels make me think OK has a fairly mild winter.

Geo makes more sense as your winter temps decrease and then it also tends to last a lot longer so your payback becomes the lifespan on a heat pump. And since you were quoted Goodman, that might be less than 10 years. Geo will also make more sense as your electric costs rise to more normal levels. At some point, electricity won't be 5 cents a KWH. Your math changes dramatically when it is 10 cents.

Given the inability to get any money safely on investments and the low borrowing costs, it make financial sense to prepare long term for inflation. So even a 30 year payback makes a lot of sense since that doesn't factor inflation -- if this is your home you plan on living in for a long time.
Heck - I plan on getting PV - it is basically a 5% ROI but that is great right now and it is a hedge against inflation

"He also mentioned that in NJ, he does not recommend horizontal loop because even if it is 8ft deep - on very cold days, system does not perform well. "

Drill for the ground source.

While the horizontal loops sound good, drilling gets you access to far more stable temperatures that do not have significant seasonal variation.

Any closed loop configuration of liquid ground loop is as effective as any other as long as it is properly designed and installed. It matters not whether it is vertical, horizontal linear 2-pipe, horizontal linear 4-pipe, slinky or whatever.

Rather than horizontal or vertical, other factors related to head (pressure drop) may be of equal or greater importance, such as, loop length & diameter, series or parallel configuration, proper header design, antifreeze type and concentration, just to name a few.

Consider all options possible. Seek out an installer that can.

Imagine.

SR