Ground Source Heat Pump Help

[Iceburg]

We live outside of Ottawa Ontario, Canada (climate zone 4)... cold winters, hot summers. We have a 4500 sq foot home (2 stories + walkout basement) on a 4-acre lot. We currently heat with oil (home + hot water). I have recently begun to research the viability of retro-fitting our home with a GSHP. One contractor has stated that it is do-able with a 6-ton unit and some minor duct work changes. Another contractor (without making a site visit) has stated over the phone that we would need a commercial unit and extreme duct work changes.

What information do I need to gather and to take into account in order to assess any proposals presented?

[HereSince1628]

1. Figure out what it takes to heat the home--hire a consultant

In addition to just cubic feet of space you've got heat loss thru windows and doors and houses will vary on how much goes out thru the ceiling depending on design and insulation...there is the issue of typical heating demand and then "peak" demand in extreme weather that needs to be met within regional expectations.

There are consultants that do this sort of work here in Wisconsin as all new homes require an estimate prior getting a building permit. These jobs by consultants aren't terribly expensive-maybe a couple hundred bucks-and the consultant works for you, not a contractor. I'm guessing they're available where you are too.

Once you know the demand that'll be put on your system you can figure out how best to meet it in a cost effective manner.

Don't forget there are installation costs as well as equipment costs...depending on how your new system is designed there may be a pretty big plumbing job to be done inside the house. House specific issues about available space to renovate for the equipment may be an issue in the cost, too.

[Iceburg]

2. Thanks...I will take your advice and hire a consultant

to perform a thorough study on the as-is system.

[MuseRider]

3. That is exactly what you should do.

We just put one in using my pond to sink the coils. We are still not done with the house so I can't tell you much about it yet since we have not run it but we got a consultant who actually helped us with zoning the house as well. We changed a few of our plans to add doors etc. to make it most efficient. Dealers are great for getting knowledge but a consultant will really get into the nuts and bolts about how to make the thing work best for you and be the best for the environment.

It may be that it will not work well for you, I guess they are not ideal in many places? Hot summers and cold winters are like our weather but I do not know how extreme yours are so I can't even say if they would compare.

[Iceburg]

4. Thanks all for the advice -- I have been in contact with a couple

of independent energy audit consultants in the area.

[lfairban]

5. The view from Ohio.

One of my nephews put in a geothermal auxiliary heat pump since they could not get a natural gas line to their farmhouse without a major upfront cost and were forced to use electricity for a primary heating source. I told one of the HVAC vendors that was giving me an estimate on a new air conditioner, and he said that my nephew's project would probably not be cost effective since the unit would probably fail before it would pay for itself.

This is not to say that your proposal is not a good one, there are probably obvious differences. However, you may want to do some additional homework about reliability issues before you commit.

[LiberalEsto]

6. Analyze the life cycle cost

How long is it expected to function and how much money will it save over that time? How soon is it expected to pay for itself, if ever? How much maintenance can be anticipated? Make sure your climate zone is factored in, along with best estimates on future fuel costs.

Then compare that to life cycle costs for standard heating equipment.

Also, how much of your property will need to be dug and disrupted for installation?

[Iceburg]

7. Again thanks for the excellent advice...

I have kept very detailed records of our oil furnace operational costs (fuel, maintenance etc) in addition to records on the downtime (due to missed oil deliveries, breakdowns etc).
We are currently averaging $6500 CDN a year in fuel and maintenance alone. Above that, we also have the cost electricity for the air conditioning and whatever is consumed by the furnace fan and motor. It will be a bit harder to separate my air confitioning costs from my entire electricity bill but I am sure that the independent energy auditor can help me with that.

[Canuckistanian]

8. What part of Ottawa do you live in?

That's where I am, too. Well, in Lanark County, actually.

But I work in Kanata.

[smellsLikeFries]

9. Also from Ottawa - here's home vendors

Also from Ottawa,

I've found only 2 vondors for GSHPs. Please post any you know of any others in the area (AquaTech ring a bell?)

Donwell construction (they built the Shadow Ridge community in Greely - all on heat pumps 10 years ago).
Earth Energy Solutions (use the Nordic DX systems and are contractors for the EcoCite eco-condos on Bank St).

The first quote I got was for $25,000. 2 Drilled holes, 60m/200ft deep, closed-loop system.

25k seems high to me. If it were 15k I'd get it at the drop of a hat (5yr pay-back period). If only the damn gov't would start their energy efficant home rebate program again. I have plans to generate the electricity needed to run a GSHP and the rest of my house (~8kW) from waste vegitable oil. No hydro bill + no gas bill == the promised land.