EPA wood furnace - Caddy

[Beno]

Hi there,

I'd like to know the opinion of this forum about Caddy - E.P.A. wood or wood-electric/oil combination furnace:
http://www.psg-distribution.com/product.aspx?CategoId=16&Id=335
http://www.psg-distribution.com/product.aspx?CategoId=17&Id=377

The Caddy has a 3.5 cu.ft. firebox and you can buy it with oil/electric backup. I saw few posts here, but it seems that no one has actually used it.
The house is a 2 storey 3600 sq.ft. located near Ottawa, Canada. This looks attractive because is cost effective, I'll have the ductwork that I can use for A/C, I can solve also the ventilation problem w/o ducts for HRV/ERV, I'll not have to create complex plumbing installations for hydronic radiant heating.
Also, should I go with oil or electric combo? Another advantage, is built in Canada.

Thanks,
Beno

 

[Todd]

I was looking at those last night. It's nice to see an EPA rated wood furnace with a fire viewing glass door. I like the mini caddy. Any idea what they cost?

 

[BrotherBart]

U.S. Stove Company is selling the exact same furnace as their Hotblast 1950 model. Hopefully it will make it to Tractor Supply like their non-EPA furnace did.

 

[laynes69]

There were some on ebay not too long ago for 1,500.00 which is cheap. They are close to 3000 through us stove. If I ever replace my wood furnace I will buy one of these. I have my current wood furnace ducted in like one of these and its a sweet setup. I could see these things heating 3500 square feet, if the ductwork is sized correctly.

 

[stoveguy2esw]

shows 73 % efficiency , but does not show particulate matter results , is this an exempt unit? it should be due to being a furnace , but they show it on the website as an "epa" unit to be certified it must have an epa "GPH" rating, if it has one i didnt find it on the website , nice looking furnace though , i wonder who is building them.

 

[BrotherBart]

6.56 GPH.

 

[karl]

Yukon-eagle.com has one that runs on wood/coal and natural gas/ heating oil. So if you forget to fill it with wood it will switch automatically to gas or oil. Plus it will automatically light the wood fire too. It's expensive though.

 

[KeithO]

Because it is exempt, one has to be cautions that it actually meets "regular" EPA specifications. Vogelzang, which makes some of the worst junk on the face of the earth, also claims to meet "EPA requirements for exempt woodstoves" which is of course completely meaningless.

The design features one needs for a good design are easy to look for: Lots of refractory, heated secondary air, good sealing around all openings and joints to avoid excessive leakage etc. The firebrick is certainly there.

 

[Beno]

From EPA site:
Caddy (duct furnacea0
Noncatalytic
6.6 (Emmisions)
63 % (Efficiency)
12000-52900 (Heat BTU)
3/19/2008

I'd like to know if this/a wood furnace can work during a power outage? My guess is not, that means I'll have to have a generator?

 

[webbie]

I'm very familiar with Yukon - decent unit, but virtually the same model they designed and sold since 1978....way before EPA standards came into effect......what we need now if the 70+% efficient furnace using the downdraft system that Harman, VC, Travis and others are starting to use - word on the street says this offers a fairly even burn cycle - and LONG burns....

But at a good price ($3000 seems high), the caddy is one of the only units out there with decent clean burning built-in.

 

[laynes69]

The caddy is around 2500 or 2700 for the list price. Its more for US Stove. I do believe that US Stove bought into the design of the caddy, cause for a while the caddy was the only epa wood furnace. They have 3 tubes above the firebox where I think the high combustion occurs. You just open a door and run a small brush through them to clear the soot. They don't require electricity for the high combustion, just to push the heat. We still keep our wood furnace going during a power outage. We turn the draft down and it acts as a gravity heater. When the power comes back on we get the blower back. I really like the idea where the ducting can be installed from either side of the furnace. Just use the main furnaces blower, and you wouldn't need one on the unit. I know the caddy can be ordered with or without a blower, but don't know about usstoves.


(broken link removed to http://www.usstove.com/proddetail.php?prod=1950)

 

[Gibbonboy]

The Caddy is $2,349 from here: http://www.barbecues.com/web/catalog/product_detail.aspx?pid=187795

Not sure what the shipping would set you back. Barring the introduction of a better and less-expensive EPA wood furnace, I'll be getting one of these in a couple more years. I currently have a US Stove wood furnace, I certainly wouldn't spend MORE than the Caddy costs to get US Stove's crap quality. My current furnace is perfectly functional, and I am happy with the way it performs, it's just made sloppily and from shoddy materials. Their smaller furnaces (Hotblast, 1557, etc.) are worse- the doors are made from sheet metal, no firebrick, just basically guaranteed to last 5-10 years and be scrapped. The Caddy will cost less than a thousand dollars more, and if they last 10 years, they're completely worth it to me.

There was also rumor about a bunch of OWB's that meet EPA standards, but I don't think that particular market is open to such ideas yet. Hard to burn skidder tires and bale wrap in an EPA stove!

 

[coppermouse]

I am looking into one of these stoves, The USSC 1950 is exactly the same if you look at the manual it is exactly the same, except for one picture the shows the company name when cleaning the heat exchanger. I checked at Tractor Supply yesterday and they can order in the US Stove for $1795 + $175 shipping (quite a bit less than the website list it for (3K)
But I was also looking at the woodchuck, it is 73% efficient. How does that stove compare? How aout the Kuuma Vaporair ?

 

[Beno]

Few questions regarding the installation of the Caddy.
1. From the Caddy I'll need 4 elbows (45 degrees each) to connect to the 7" flue pipe. Is this number of 45* elbows acceptable? They will all be in the utility room on first floor (no basement in the house).
2. The manual recommends 2 feet clearance on the sides of the furnace and also at the back, and 4 feet in the front. Are these mandatory? What if I have only one foot clearance (sides and back) ?
3. Since there is no basement, I plan to use 5" insulated ducts that will go through the open web floor trusses, and will come out on the first floor with vents placed on the ceiling (first floor only). Is this location of the vents (on the ceiling) OK? The rooms are 9 ft height.

Thanks,
Beno

 

[laynes69]

Well the caddy is best used as a add-on. Do you currently have a furnace? The elbows sounds okay, but also depends on your draft. With it being an epa stove, draft would need to be up to par. As far as clearance, if its in the manual, then yes you need those clearances. I would assume thats for combustables. So if the manual calls for 2 feet to combustables, then 1 foot is not enough. The ceiling is the worse place to install ducts, only because heat rises. It will make it much harder to heat the home this way. If it would be your only option, then use ceiling fans to help push the air down. Are the insulated ducts flexable? If so you can't use them with the furnace. With a wood furnace you need to follow the plenum and duct clearances because of the high temps. If you have a power outage, then your ducts could get too hot. With a furnace that can push close to 140,000 btus, its very important to follow clearances.

 

[Beno]

Would you recommend to buy the Caddy with the oil backup? This is a new construction.

 

[Gooserider]

Would you recommend to buy the Caddy with the oil backup? This is a new construction.

If it's new construction, are you choosing between the Caddy w/ oil backup, or using a second furnace for backup? (or not having a backup?)

I'm not an expert, but I would say that it is essential to have a "conventional" heat backup, no matter how dedicated you are to burning. Most mortgage places will require it, and I think it's smart just because you won't always want to be home to feed the fire.

That said, it comes down to a question of tradeoffs...

Which would cost more? The Caddy w/ backup, or two seperate furnaces?

Which would take up more floor real estate for both the unit(s) and the associated plumbing?

How do the oil burning efficiencies compare? My understanding is that the Caddy oil side is less efficient than a modern standalone unit, but I could easily be wrong. If there is a difference, how big of an issue is it? If the oil only burns a little bit each year, then efficiency shouldn't be a big concern. If the oil sees heavy use, then it is...

What would the stack requirements be for each approach. I know for seperate units you'd be required to have separate flues (though the oil burner could be power vented) - what about the Caddy?

Etc.

I don't know that the Caddy type boiler would be my first choice in heating systems, but if it was, and there were no reason not to, I would probably be inclined towards the combo approach, but I don't feel like I know enough to make a strong recomendation either way.

Gooserider

 

[elkimmeg]

Beano I got to run back to work but there are some serious flaws in your planning clearances issues no discussions of combustion air ceiling feeds no mention of returns the plentum conditions no flexible duct work can be used with a wood fire furnace I would have to read that manual and apply code and then common sense of installation. before anyone can advise of how you plan to use that system.. I don't know if reduced neclosures apply to furnaces plus code also requires distances for servicing lots of issues to resolve here

 

[webbie]

Would you recommend to buy the Caddy with the oil backup? This is a new construction.

I would have to look carefully at the oil setup - some multi-fuels are not set up well on the "old" fuel.

Please keep in mind what others have said - you must use metal ducts only with wood furnaces, and the clearances are strict - usually 6" or more from the plenum, then reducing to 2" and then 1" depending on how far from the furnace. As Elk said, check the manual - it MUST specify this.

 

[Beno]

Hi there,

A couple more questions:
1. During a power outage, can you use somehow the wood furnace to cook/heat some food?
2. I spoke with a builder who said that for a 3600 sq.ft. the ductwork will be about $9000. Is this a reasonable price? (Seems high to me)

Thanks!

 

[Gooserider]

Hi there,

A couple more questions:
1. During a power outage, can you use somehow the wood furnace to cook/heat some food?
2. I spoke with a builder who said that for a 3600 sq.ft. the ductwork will be about $9000. Is this a reasonable price? (Seems high to me)

Thanks!

First off, I've moved this thread to the "Boiler Room" which is more appropriate for "whole house" type heating appliances.

As to your questions...

#1. I don't know but I would consider it a less than optimal approach. Presumably you could stick some things into the firebox and heat them that way, but I don't know how feasible that is. I would hope that the unit would be well enough insulated that it wasn't useful to put something on top of it, since you'd be wanting all the heat to go into the air ducting. I suspect that you would be far better off to get one of those Coleman "suitcase" stoves.

A more important question is what the system will do for HEATING during a power failure... I am not an expert, but from reading some of the other BR threads, I know there is concern about overheating in the event of a power failure as your heat distribution system will quit, but unlike an oil or gas burner, a wood fire doesn't go out when the power does... This is definitely an issue for the boiler people, I don't know if it is for the hot air folks, although you'd still have to worry about heating the house.

2. Never priced ducting, haven't the foggiest. Hopefully some of the others here will have a better idea of how to spec the job and what to pay for it.

Gooserider

 

[laynes69]

Some units have removal side panels incase of a power outage. This way it helps keep the furnace a little cooler. We have had the power go out here and our furnace will heat somewhat, but I really damper it down during an outage. The caddy has insulated sides, so the only place for the heat to go is out the top. I have heard of people who have added a relay that when the power goes out a door in the plenum opens up. I've never done it myself though. The clearances on ducting are important due to power outages and potential heat. Last year, or maybe 2 years ago I got a quote for ductwork in our house. It was 3200 low and 3700 high. I did it for 1,200 dollars. Its important when installing ductwork to have little static pressure in the ducts. If its undersized it will kill the blowers and furnaces, Very important to be sized right. Another thing is I would have a main furnace and use the caddy as a backup. I wouldn't get the elements in it. What if the elements went out in the caddy? I know by experience that the setup of the caddy is made to be installed in series. Also very important for the ducting to be sized correctly for the caddy. If you are serious about getting a caddy and ducting, then have them install the woodfurnace when they do the ductwork. Not every HVAC person will know how to install something like that. I'm 25 and I had to explain how my woodfurnace works with main furnace because they couldn't figure it out. When they seen my ductwork I installed, they offered me a job. It will be an excellent setup, but plan carefully and follow all manuals and you will be okay. Now I think the caddy comes from Canada??? But on page 25 of the installation manual it shows that the oil backup and the woodfurnace share the same flue. The oil flue is above the woodfurnace flue. I'm not sure about this setup, But thats what it shows. If thats the case then its 1 flue.

 

[Beno]

It looks that the equivalent of the Caddy is the Hotblast EPA model 1950. Yes, Caddy is produced in Canada (Quebec) and that means plenty of dealers in my area.
I will buy the Caddy with oil or electric backup, to have only one furnace. We plan to heat mainly with wood, so I am not sure if it's worth to go with oil (one flue). Now, I have a few questions:
1. What is special/different when you design the ductwork for a wood furnace? Just to respect the clearances, right?
2. I'd like to have a crawl space (5 ft height), where the furnace sits. Will be possible to take the hot air plenum through the crawl space ceiling and go from there with the ducts to the first and second floor?
3. What is the sq.ft. that you heat with the Hotblast ?
4. For how many years do you have the Hotblast and if you had any special problems?

Many thanks!

 

[Gooserider]

Beno, you need to download the Caddy manual, or the manual for whatever furnace you are planning to use and see what they say about using a single flue - that is the ruling document. It may also have the answers to your questions about clearances and plenum design.

Also it may be worth considering some other points that I've seen - I don't claim to be an expert, but I've seen multiple seperate mentions of these issues.
1. Many comments suggest that multi-fuel units often sacrifice performance with one (of both) fuels as it isn't really possible to design a firebox that is optimal for both.
2. I've also seen things suggesting that the oil burner "guns" in wood / oil units are very susceptible to damage when burning wood, unless they are removed, but removing the oil gun sacrifices the use of oil as backup when one unexpectedly looses the wood heat...
3. With a multi-fuel unit, you have a "single point of failure" heating system - if anything goes wrong, your entire heating system is out of commission. W/ seperate units you have more redundancy.

This would all incline me more towards a dual unit setup (which would require dual flues)

Either way, if doing new construction, I'd consider it good "future proofing" to include two flues, or at least the space for them, in your design, as that would allow you or a future owner more options for changing things in the future without major hassles.

Gooserider

 

[laynes69]

I have an older model. They are still being produced today, they heat well but if you don't know how to burn them correctly can be a dirty burner. You cannot have any restrictions in pressure when you duct an add-on like this in. Everything that goose has concerns with is legit. I wouldn't want a single thing to go bad on me and lose my heat. And the thing with the clearance, the units are 4 feet tall. The unit will not fit in a crawl space. Have you personally seen them? They are large units. If you want to get the best setup get a oil furnace thats high efficiency and duct in the caddy. Dual flue and less problems for things to go wrong. I heat 2400 square feet with my furnace. That furnace is designed for 3000 square feet. Now if you install it correctly and have good tight construction then if planned wisely it should do okay. Heres the thing. The unit is designed for 3000 square feet. If you get the wood/oil combo, What if it couldn't keep you home warm? If it was me I would get a oil furnace sized correctly for the home and if you can install with full clearances then duct in the caddy. I'm afraid that installing something like this in a crawlspace could be a disaster. At a potential for 140,000 btus, do it right. If it wouldn't work for the home, then I wouldn't make it work.