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bobmans
Oct 10th, 2007, 12:50 AM
Anyone here have any experience with heat exchangers? I live on a typical sub-urban lot and would love to have to have a geo thermal heat exchanger but considering to size of my property it is probably not practical to install. I have read about air exchangers and would like anyones opinion who has installed one of these units.

notanexpert
Oct 10th, 2007, 12:53 AM
A geothermal system on a small lot is very expensive to install because it involves drilling deep holes to bury the heat exchanger piping vertically underground. Sometimes its not even feasable if you can't get the machinery into position. At current energy prices it does not make sense.

dark169
Oct 10th, 2007, 12:21 PM
I've seen a couple installation and a customer of mine in a previous life installed a bunch, almost all of them where on farms or rural lots with land to us. A couple used drilling to lower the piping down into the ground. Most of the time when the owners considered the cost of a gas line or propane tank installation the extra 10-15k on top of their high end hydronic heat/cooling systems made sense.

btw, the proper term is heat pump.

I looked into them for my parents campground that uses electricity for heat/water-heating and the COP one can expect is around 4, so after you install the system every kW of eletricy you used for heating/water-heating does 4 times as much heating. The cost of the system really holds one back though.

Air/air heat pumps can't do the job in Canada, they are used all over more temperate areas where you need heat too keep the chill off at night when it dips to 5C but dont work at the -20C days we get here.

brunes
Oct 10th, 2007, 12:32 PM
I've seen a couple installation and a customer of mine in a previous life installed a bunch, almost all of them where on farms or rural lots with land to us. A couple used drilling to lower the piping down into the ground. Most of the time when the owners considered the cost of a gas line or propane tank installation the extra 10-15k on top of their high end hydronic heat/cooling systems made sense.

btw, the proper term is heat pump.

I looked into them for my parents campground that uses electricity for heat/water-heating and the COP one can expect is around 4, so after you install the system every kW of eletricy you used for heating/water-heating does 4 times as much heating. The cost of the system really holds one back though.

Air/air heat pumps can't do the job in Canada, they are used all over more temperate areas where you need heat too keep the chill off at night when it dips to 5C but dont work at the -20C days we get here.

Yeah it is hard ot justify a retrofit. But when building it is often well worth it to put in a below ground heat pump, because not only will it save a ton on power, but it will add to the value of the house.

eelfliw
Oct 10th, 2007, 11:56 PM
I have read about air exchangers and would like anyones opinion who has installed one of these units.
Can you clarify what you mean by air exchangers? Are you referring to heat recovery vents used on some R-2000 homes?

bobmans
Oct 11th, 2007, 12:44 AM
As corrected by a previous poster I should have called it a heat pump. I am just looking for something that is environmentally friendly and will save me a few $$$ in the long run (because in essence the energy is 'free' once installed minus the cost of running the pump). I expect that energy costs will only continue to go higher in years to come and the 'payback' period may be shorter than the 20 years or so indicated on many websites.

dark169
Oct 11th, 2007, 12:34 PM
Can you clarify what you mean by air exchangers? Are you referring to heat recovery vents used on some R-2000 homes?

I think he was referring to heat pumps that use the outside air as the source. Kinda like running a fridge backwards. They are used in parts of the US for both cooling and heating.

But heat recovery ventilators are a great way to save energy.

notanexpert
Oct 11th, 2007, 06:09 PM
I think he was referring to heat pumps that use the outside air as the source.
...

No, I believe he's talking about a heat pump that uses the temperature underground to warm the house and cool the earth. Expensive to install, a bit cheaper if you have enough land to bury the pipes horizontally by just digging a trench. On small lots, the pipes have to be installed vertically by drilling down, and that is most likely too costly compared to the potential energy savings.

bobmans
Oct 13th, 2007, 01:20 AM
My question was originally posed to anyone who has either set up. If a geo-thermal system is not practical from a cost standpoint due to the smaller size of my lot then I would be interested in an air exchanger set up even if it only supplemented my current natural gas furnace system. I have read that these systems can operate in temps that are well under freezing. Even if they don't, if I can use them when them temps are above 0 then I would think there would be some sort of savings. Anyone here doing this?