3700 sq ft Wood Furnace Add On?

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Beaster

New Member
Nov 10, 2019
8
Saskatchewan, Canada
Hey guys,

I live in Saskatchewan Canada and plan on building a 1860 sq ft bungalow with a full ICF basement this summer. I would like to use a wood furnace add on to a natural gas furnace to help cut down my heating bill.

I think I have it narrowed down to the Kuuma Vapor Fire & PSG Max Caddy. They are both rated for 3500 sq ft, however, the price difference is quite substantial. The Caddy is listed at $5,399.00 CAD & the vapor fire is listed at $5,695.00 USD. So by the time I pay the exchange, freight and probably some duty, I'll be looking at a pretty big pill to swallow.

From everything I've read about the VF, it's the best in the business and I'd love to have one; but at what cost??

Does anyone have either of these installed in a similar size house & how does it perform? Has anyone here taken delivery of a VF in Canada, what was the total bill?

Thanks.

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I'd do the heat loss calcs first to determine how many btus the house will need at both the design limit (say -25ºC) and normal winter temp (say -7º). With too much heat the furnace may be smoldering more than burning.
 
Are you doing the whole walls with ICF or just the basement?

I think with new construction like that and access to NG, I would just add a nice wood stove to supplement with. Should take very little to heat it.

And maybe throw in a mini-split if A/C is a consideration, since they can do both.
 
Only the basement will be ICF. I had pondered the thought of a wood stove in the living room. But would rather throw wood through a basement window rather than carry it up into the house.

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Only the basement will be ICF. I had pondered the thought of a wood stove in the living room. But would rather throw wood through a basement window rather than carry it up into the house.

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Beaster,
If you are building new and have the opportunity to do it, put a cut down door with an egress well to get your wood in. My parents threw wood in a window and it was a PITA. The 1/2 door works great with a chute to toss the wood down.
Wood Chute.jpg
I am very happy with my standard Caddy. We are heating 1700 sq. ft. ranch with a full basement. It is just the right size for our home in Wisconsin. I've heard nothing but good about the VF. I too was considering it, but the price differential is what steered me to the Caddy.
 
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Beaster,
If you are building new and have the opportunity to do it, put a cut down door with an egress well to get your wood in. My parents threw wood in a window and it was a PITA. The 1/2 door works great with a chute to toss the wood down.
View attachment 251742
I am very happy with my standard Caddy. We are heating 1700 sq. ft. ranch with a full basement. It is just the right size for our home in Wisconsin. I've heard nothing but good about the VF. I too was considering it, but the price differential is what steered me to the Caddy.
Great thinking with the cut down door, I would have never thought of that!!

I'm thinking I'll probably end up going with the Caddy. I fired Kuuma an email the other day to see if I could get an estimate on what it would cost to get it up here. Fingers crossed it's not as bad as I think it'll be.

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Personally, I'd spend all the money I could afford on great insulation, triple pane windows, and ideas from the pretty good house concept. I think if you do some of those things you could probably get away with a smaller wood furnace. A T2 is about half the cost of the furnaces your are quoting.
 
Well so much for that idea. After reading the Max Caddy's installation manual online, I discovered that a parallel system is illegal up here in Canada.

Now that I'm looking at a series install I have a couple more questions.

I won't need the Caddy fan, as the system will be using the NG furnace fan right?

What kind of NG furnace should I be looking at, a variable speed fan or a fixed speed fan?

When the NG furnace kicks in, is the caddy wired to slow the fire right down or will it want to choke the fire out?

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I won't need the Caddy fan, as the system will be using the NG furnace fan right?

What kind of NG furnace should I be looking at, a variable speed fan or a fixed speed fan?

When the NG furnace kicks in, is the caddy wired to slow the fire right down or will it want to choke the fire out?

Beaster, mine is set up in series, using the LP furnace fan. It is wired to run the fan at a reduced speed when the wood furnace calls for heat. I control mine by simply setting the LP furnace at a lower temp, about 5 degrees (F) lower than the wood. If the fire burns down the house has to cool enough for the LP to kick in.

I'm sure there are more elegant solutions, and someone will probably chime in with that detail, but the set-up I have is simple and it works fine.
 
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Ideally with a series install, both units should not need to run at the same time. Therefore, setting the temperature a few degrees apart. By the time the fire dies down, the central furnace would run. In Canada, you would require an interlock. That way when the woodfurnace is running, the central furnace won't operate. I've ran both at the same time with my old setup and there wasn't an issue (I didn't have an interlock installed, even though I have one).
 
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Hey guys,
I live in Saskatchewan Canada and plan on building a 1860 sq ft bungalow with a full ICF basement this summer. I would like to use a wood furnace add on to a natural gas furnace to help cut down my heating bill.
I think I have it narrowed down to the Kuuma Vapor Fire & PSG Max Caddy. They are both rated for 3500 sq ft, however, the price difference is quite substantial. The Caddy is listed at $5,399.00 CAD & the vapor fire is listed at $5,695.00 USD. So by the time I pay the exchange, freight and probably some duty, I'll be looking at a pretty big pill to swallow.
From everything I've read about the VF, it's the best in the business and I'd love to have one; but at what cost??
Does anyone have either of these installed in a similar size house & how does it perform? Has anyone here taken delivery of a VF in Canada, what was the total bill?


Have you considered a Ardent Energy Furnace? I installed one for my mother-in-law in 2013 and have been very impressed with its performance. The furnace has been around for 25 or 30 years, is made in Canada and it is CSA approved. We got ours through Home Hardware.
 

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Would it be any easier just to run some ducts just for the wood fired & have 2 separate systems?

I would definitely consider a second duct system dedicated and optimized to the wood furnace. That way you could run them both at the same time, you could have a completely independent backup system if one failed somehow, and you could optimize the static pressure for each blower. The wood duct system doesn't need to be as extensive as the central system and the central system could run in fan-only mode if the temperatures became uneven or to filter the air. With today's high tech variable speed furnaces, I wouldn't want to mess with using it for the wood furnace blower.
 
Have you considered a Ardent Energy Furnace? I installed one for my mother-in-law in 2013 and have been very impressed with its performance. The furnace has been around for 25 or 30 years, is made in Canada and it is CSA approved. We got ours through Home Hardware.
I don't see any efficiency numbers in their brochure. My bet is that it is about half ( 30 - 40% ) as efficient as the Caddy line.
 
Beaster, mine is set up in series, using the LP furnace fan. It is wired to run the fan at a reduced speed when the wood furnace calls for heat. I control mine by simply setting the LP furnace at a lower temp, about 5 degrees (F) lower than the wood. If the fire burns down the house has to cool enough for the LP to kick in.

Is your LP furnace fairly new? Just curious how much of a headache it is to reduce the blower rpm for when the wood furnace is running.
 
Napoleon also makes a wood/gas furnace combo.

 
Is your LP furnace fairly new? Just curious how much of a headache it is to reduce the blower rpm for when the wood furnace is running.

Both furnaces were new in 2016. The LP is a Rheem Prestige. The system was installed by the contractor who installed the entire system so I can't speak to how difficult it is, but I get the impression it is not difficult to do.

I like that our system works with all the same duct work as the gas furnace. There are trade offs to every set-up, but by using the same duct system I have the same filtration, cold air returns & heat in every room and we have a heat recovery ventilator. Everything works the same whether we are heating with wood (we almost always are) or LP.
 
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