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HVAC Forums => HVAC Help => Topic started by: Dave C on August 30, 2014, 06:55:14 PM

Title: Building a new home. How to heat?
Post by: Dave C on August 30, 2014, 06:55:14 PM
Hello All,

I hope I have come to the right place for some help.  My first post with plenty of questions... :-\

We are building a new home in central Ontario and I am trying to figure out the best way to heat the house.  NG is not an option (I wish it was) as we are building at a remote lake site.  The heat loss calculation is 80,000 BTUs and the house is a 2 story home about 2,700 sq. ft., 1900 main floor and 800 upstairs.  We plan to stay here for 20 years or more, so I want to keep long term planning in mind.

The way I see it, we have five choices or combinations thereof:

1. Propane furnace.  We will have at least a small tank as my wife likes to cook with gas, but after looking at last year's nightmare costs for propane, I am reluctant to go the propane furnace route!  The plus is less yearly maintenance and service calls.

2. Oil furnace.  I am not sure if a new install has any insurance negatives, but my calculations show that a 95 AFUE oil furnace would be the most cost effective, excluding a lake source heat pump. 

3. Wood.  We have lots of wood and it is cheap here, but I would need a backup (oil or propane) as I don't want to spend all my time feeding a firebox.

4. Lake source heat pump.  The upfront initial cost is $38,000!   That's a lot of oil, and with Ontario electrical rates expected to go way up over the next few years, is it really cost effective?

5. Air to air heat pump with backup.  I have looked at two; the Mitsubishi Zuba and the Carrier Greenspeed.  They are not cheap, and although the Zuba appears to be the best performer at low temperatures, but it has a maximum output of 40,000 BTUs.  The Greenspeed is an unknown to me and appears to perform better in climates closer to that of North Carolina.

I am thinking that maybe my best bet would be to install a Napoleon NZ6000 fireplace on the main floor, a small propane tank for cooking, and a forced air oil furnace with an oil hot water tank.  The Napoleon fireplace would help supplement the furnace. 

If anyone can help, my questions are:

1. Does what I want to do make sense?  Is Propane any better than oil? Vice versa?

2. Any idea on what the payback would be on a lake source heat pump?  Are they really worth that kind of investment, especially in Ontario where the electrical rates could go sky high?

3. I am trying to think of a way to help move the heat from the fireplace around the house.  Would installing a cold air return (with a manual damper) close to the ceiling in the room with the fireplace and let the furnace fan run work to move heat?  Is there a better method (such as just leaving the cold air returns at floor level)?

4. Older homes used to have transoms above the doors to help move heat around.  Does it work and should we look at building these in to our rooms?

5. Does anyone have the Carrier Greenspeed heat pump installed in a cold climate?  Are they worth the cost?  And again, with increased electrical rates, do you think they will still be cost effective?

6. Does anyone have a 95 AFUE oil furnace installed?  What do you think of it?

Sorry for all the questions, but I am feeling a bit overwhelmed.  Any and all opinions are greatly appreciated!

Thanks,

Dave
Title: Re: Building a new home. How to heat?
Post by: Admin on September 02, 2014, 07:11:44 PM
In Ottawa natural gas is the cheapest followed by propane then electricity, leaving oil as the most expensive.  Natural gas will increase 40% as well, but will still be the cheapest option.  Oil never used to be the most expensive option so who knows what will happen in 20 years.

I would want air conditioning so the choice would be simple for me.  I would install a dual fuel system.  I would use a heat pump and heat until the outdoor temperature exceeds -12C to -15C.  Then use a high efficiency modulating propane furnace with ECM blower to heat when the heat pump is in its defrost mode or when the outside temperature is below -15C.  With electricity rates rising you may actually be better off running the propane furnace all winter.  It gets hard to compare electricity because the rates fluctuate depending on the time of day.  I wouldn't even consider heating with oil.  Wars are fought over that commodity and I think it will continue to be the most expensive option.

I know some people who run their heat pumps to -25C.  The Carrier Greenspeed claims to offer efficient heating into the teens.  19F is around -7C.

A propane fireplace is not as efficient as the propane furnace I recommend.  I would only install fireplaces for decorative purposes and as a source of heat should you lose power.  Being a new house you should have a proper duct design to ensure the forced air system heats the entire home evenly.  Then, if you did run the fireplaces you could leave the furnace fan running continuously which will help circulate the hot air around the house, unless of course the power was out. 

I attached a couple 2014 energy comparison charts below.
Title: Re: Building a new home. How to heat?
Post by: Dave C on September 04, 2014, 03:25:33 PM
Thank you for your reply! 

I wish we had NG, but propane is the next best so I think we will go with that and a wood burning stove or fireplace.

Dave