EPA wood furnace - Caddy

[Jim Post]

I'm happy to report that gasifiers don't NEED storage....it's nice, but c'mon you can achieve a clean burn w/o storage...it just requires you to think a little bit when loading....similar to how you would tend a wood stove. It works for us anyway.

 

[Eric Johnson]

The Caddy specs on the combination unit are 73 percent efficient with wood and 82 percent with oil. That's not bad for the wood side and while 82% is pretty average for an oil burner, it's a good number for a combination unit.

Gasifiers tend to claim high 80s to very low 90s in overall efficiency.

Tarm's Excel 2000 is a combination oil/conventional wood-fired boiler. They claim 80% on the wood side and 85-87 with the oil. New Horizon also has a selection of conventional boilers, as does Marathon.

 

[Beno]

How can you supply DHW w/o storage?

 

[Eric Johnson]

That's true about clean burning without storage and the firing strategy being similar to a wood stove or furnace. I think what you sacrifice without storage is efficiency, because if you produce heat at the wrong time, it tends to get wasted. A good firing strategy helps keep that to a minimum. Gasifiers with storage are also supposed to last longer, though I'm not completely clear on why.

If you put a heat exchanger on a conventional hot water heater and pump hot water from the wood boiler through it, Beno, it will fill your water heater tank with hot water and keep it that way. That's what I've done for the past 15 years, and we never run out of hot water.

Where the tank comes in handy for DHW is in the summer because you can fire your boiler up once a week, heat the tank, and live off that.

 

[Jim Post]

I have a sidearm heat exchanger on my electric water heater....provides an endless supply of hot water.

 

[BrownianHeatingTech]

1. Based on the code in my area, I need ventilation to each room if I don't have a furnace with air ducts. If I have a furnace, the ventilation will be done by the furnace fan to the rooms, and I'll have to supply outside air to the furnace. So, even with hydronic heating I need to install ducts (smaller) for ventilation. Cleaning them may be harder than with the furnace ducts.

I'd like to read the actual code on that.

2. I thought that the wood boiler comparing in efficiency with a Caddy EPA wood furnace has to be a gasification boiler. Can you please recommend a very efficient (non-gasification) wood boiler?

Biasi.

I expect there are plenty more that can meet the Caddy's efficiency, with ease.

Joe

 

[Jim Post]

In the summer, I revert to electric....but I am thinking with a little scheduling we could fire the tarm for our hot water needs. :bug:

 

[Eric Johnson]

I have a sidearm, too, JP. They're easy to build and pretty much bullet proof.

I don't know if yours feeds through gravity but if it does, you might want to consider putting a circulator on it for summertime heat stashing. I doubt the gravity feed (which is the way mine is set up) can transfer heat fast enough to keep up with the boiler. Maybe add another/bigger tank or an indirect. That way you could probably stash enough HW for a couple of days with one firing.

 

[Beno]

9.32.3.7. Ventilation Systems Not Coupled with Forced Air Heating Systems
(1) This Article applies to a mechanical ventilation system in a dwelling unit that,
(a) does not contains a forced air heating system, or
(b) contains a forced air heating system and the forced air heating system is not used for circulation of the ventilation air.
(2) The mechanical ventilation system shall introduce air to and circulate air throughout the dwelling unit in compliance with this Article.
(3) The mechanical system in this Article shall include a heat recovery ventilator installed in accordance with Article 9.32.3.11.
(4) Outdoor air shall be distributed by a ductwork system from the heat recovery ventilator required in Sentence (3) to each bedroom, to any storey without a bedroom and, if there is no storey without a bedroom, to the principal living area.

This is for Ontario, Canada.

 

[Jim Post]

Ok....I have to consider that...I've never fired the tarm in the summer so that would present a whole new set of operating issues.

 

[Beno]

1. Can you please recommend an efficient wood boiler for my location: Ontario, Canada ?

2. Can I use instead of the large water tank an indirect like this?
http://www.heatexchangersonline.com/indirectwaterheater.htm
http://www.thermomax.com/tkindex.htm

 

[BrownianHeatingTech]

9.32.3.7. Ventilation Systems Not Coupled with Forced Air Heating Systems
(1) This Article applies to a mechanical ventilation system in a dwelling unit that,
(a) does not contains a forced air heating system, or
(b) contains a forced air heating system and the forced air heating system is not used for circulation of the ventilation air.
(2) The mechanical ventilation system shall introduce air to and circulate air throughout the dwelling unit in compliance with this Article.
(3) The mechanical system in this Article shall include a heat recovery ventilator installed in accordance with Article 9.32.3.11.
(4) Outdoor air shall be distributed by a ductwork system from the heat recovery ventilator required in Sentence (3) to each bedroom, to any storey without a bedroom and, if there is no storey without a bedroom, to the principal living area.

This is for Ontario, Canada.

That's not every room.

1. Can you please recommend an efficient wood boiler for my location: Ontario, Canada ?

Need a lot more information than a geographical location. What will it be heating?

2. Can I use instead of the large water tank an indirect like this?
http://www.heatexchangersonline.com/indirectwaterheater.htm
http://www.thermomax.com/tkindex.htm

Yup. The larger the storage, the better, but there's no particular minimum.

Joe

 

[mtnxtreme]

Thanks, so the basis for the extra cost of a boiler versus a Caddy HVAC is the greater efficiency and longer life. I definetely wanted HW, I have ducts now, and the HVAC drived my allergies crazy. So for boilers, are Tarms the ticket compared to AHS etc, who's got the best deal for the money?

 

[Eric Johnson]

When I bought my boiler, about six months ago, the EKO had the best price. But like the Tarm, it's an import, so the weakening dollar has driven up prices recently. For regular gasifiers (Tarm, EKO, Wood Gun, Econoburn), I'd be willing to bet that Wood Gun is still at the high end and EKO at the low end, with Tarm and Econoburn probably pretty close to each other in the center. Just a guess. As to true value, everybody's got an opinion, many of which are regularly expressed in threads on this forum.

EDIT: I forgot the BioMax, another import. I believe they're a bit cheaper than EKOs, possibly with more features.

 

[Beno]

We are in the design phase, so we consider different options. I'd like to have a wood based solution with oil backup. I chose the Caddy wood/oil because there are many dealers for Caddy in my area. This will be a 2 storey house, ICF walls, energy efficient, passive solar, 3600 sq.ft. Here are the options I see now:
1. Caddy wood/oil for heating + oil heater for DHW.
2. Caddy wood/oil for heating + smaller wood/oil boiler for DHW.
3. Wood/oil boiler for heating and DHW

The house will have no basement, so not much storage room. Your advice is greatly appreciated.

 

[Eric Johnson]

You seem committed to the Caddy, but personally, I'd go with hydronic heat in a heartbeat. It's such a superior way to heat your house and hot water than forced air, and it has virtually unlimited potential for expansion and modification down the line. You can mate solar up to hydronic heat easily, and probably geothermal for all I know. Pumps are a lot more efficient than blowers, and your options with water are so much more plentiful. You can go with infloor radiant, cast iron radiators, hot water baseboards (copper fin tube and cast iron), etc. The list goes on and on. Looking forward into an uncertain energy supply and price scenario, I think you're way ahead with the efficiency, convenience and economy of hydronic heat.

I'd get a bare-bones oil burner and a good gasifier and be done with it. Design a place for a tank, whether you put one in right away or not. The big problem with combination boilers, in my opinion, is that if they spring a leak, you're suddenly out of options. Plus, no matter what the mfg claims, you're always going to make compromises on one side or the other--or both--with a combo.

This would all cost more, obviously, but if you think of it like choosing the insulation for your new house, it's basically the same decision: Pay more up front for longterm savings and comfort.

 

[Beno]

I agree with you Eric, in fact this was my original plan. The only thing that made me change my mind from wood boiler was the lack of dealers/support for indoor efficient wood boilers in the area where I live, Ottawa, Canada. I have no explanation for this. The Caddy is made in Quebec, not far from us.

 

[Eric Johnson]

I'm sure there are plenty of competent heating contractors in Ottawa who could fix 95% of anything that could possibly need attention. As far as maintenance on a gasifier, there's really not much to them. No moving parts other than the blower, which can be replaced with about four screws and a couple of wire nuts. Any reasonably handy person can do all the maintenance and repairs that don't require welding. So I wouldn't let that weigh too heavily in your decision.

But it sounds like fun. Good luck with whatever you decide to do and let us know how it works out.

 

[mtnxtreme]

When I bought my boiler, about six months ago, the EKO had the best price. But like the Tarm, it's an import, so the weakening dollar has driven up prices recently. For regular gasifiers (Tarm, EKO, Wood Gun, Econoburn), I'd be willing to bet that Wood Gun is still at the high end and EKO at the low end, with Tarm and Econoburn probably pretty close to each other in the center. Just a guess. As to true value, everybody's got an opinion, many of which are regularly expressed in threads on this forum.

EDIT: I forgot the BioMax, another import. I believe they're a bit cheaper than EKOs, possibly with more features.

I can't find a dealer or pricing , for the biomax, got a link?

 

[Eric Johnson]

This is the only place I know of:

http://www.newhorizoncorp.com

 

[Beno]

Eric, great support work, I really appreciate it. I'll start to look seriously into the Tarm.

 

[mtnxtreme]

So the Biomax and EKO are wood only. I'm interested in wood/oil combo units. So I'm limited to Tarm and AHS?

 

[Eric Johnson]

For gasifiers, it looks that way. There are plenty of non-gasifying wood/oil/gas combos on the market. I'm not sure if Econoburn offers a combo model.

 

[Beno]

Will one indirect be enough for the TARM to supply both DHW and hydronic heating? The DHW and hydronic heating must have different loops, will I need 2 indirect water heaters for that? I try to figure out how the piping will go. Or maybe the water heated by TARM directly in its jacket will be used for hydronic heating and the indirect is used only for DHW? Thanks!

 

[Eric Johnson]

I'm a little confused. Typically, the indirect is one zone (or loop) on the system, among others. But it doesn't have to be. You could run everything through the indirect's heat exchanger before sending it into the house zones if you like, or put in a three-way zone valve to direct the flow of water where it's needed. For DHW, all you would need is one indirect. If you are planning to install another one to serve as hot water storage, it's not going to be much of a benefit, because there isn't that much capacity in most indirects. But just for the sake of discussion, if you did that, there are a number of different piping strategies that you could use, depending on your needs.

That's one great thing about hydronic heat--you can do a lot of different things with it--often simultaneously.