Underground Poly pipe for heat/cooling?

[WStayton]

fuelfarmer:

  FWIW, my neice and her husband got tired of being slaves to the fuel oil company, so they purchased a commercial heat-pump driven gound-energy heated/cooled system for their large (3500 sq ft + / - ) in the suburbs of Rochester, NY.

  Their commercial system uses a 1000 foot loop of somewhat smalller tubing than you have - something like 1.5" or 1.75". This was installed using some sort of water blaster  running within the plastic tubing so they PUSHED the whole length into and then out of the small hill behind their house.  I didn't see it done, but apparantly the nozzle and the hose that fed it was sufficiently smaller than the tubing being installed that the water and displaced soil was washed back out of the hole being dug, through the tubing being installed.  Since one of the best crops in Upsate NY is rocks, I was surprised that this worked at all and that they didn't have a problem with small stones getting lodged in the tubing, but it DID work! <grin>

  The loop circulates a glycol/water media, and is used forboth heating and cooling.

  The results have been astounding!  There total electric bill vs electric+fuel-oil previously have been more than cut in half, for both winter and summer.

  Not sure how the foregoing would apply to running air through the tubing, but the system seems to work well with a liquid exchange media.

  The control system, and getting it calibrated and adjusted was a b!%@h, BTW!  It is microprocessor driven and has a myriad of inputs and the ability to close every valve in the whole system and start-stop-reverse every pump in the whole system plus I think it sews on buttons AND walks the dog!!!  And, until it was tweaked, a lot, it didn't do ANYTHING well.  Think three months of too-hot/too-cold/too-humid/too-dry/etc./etc., but AFTER it was finally completely calibrated and working optimumaly, the result was worth the aggrevatioin according to me neice and her husband.  The total system consists of the in-ground loop and a few solar electric panels and a few solar-hot-water panels, the latter for warming the pool.

  Not sure if this will help uyou, but what you are trying to do IS possible!