Which add-on wood furnace?

[fields_mj]

I have an old (circa 1980) add on wood furnace that I've been using for, well lets call it several years.... It has done a great job for me, but it will either need to be replaced or rebuilt in the next few years. The design is VERY similar to the Clayton add-on wood furnace that was popular for so long. It looks like US Stove has discontinued that model (1802g), so I'm looking for other suggestions. So far, I'm looking at the USSC Hotblast, Kuuma Vapor Fire, Royall/Energyking, Fire Chief, and Shelter.

Shelter - Based on the reviews, appears to be junk.

USSC Hotblast - looks like a knock off of a Clayton, and may no longer be available. Not EPA certified for using with wood.

Royall/Energyking - Don't see much information. 75% more expensive than a fire chief with no mention of air being preheated and supplied for a secondary burn. Looks like it could be nearly identical to the 1980 Energy Mate that I'm using now.

Fire Chief - Looks like it only uses 6 fire bricks, and they lay on the bottom where they are likely to be broken while adding wood. Forced draft which I have mixed emotions about. Supposed to have a secondary burn chamber, but I don't see how they are pre-heating the draft air. Need to understand how they are trying to do this before I'd be willing to go this route. Also one of the cheapest models.

Kuuma Vapor-Fire - Seems to have a strong customer base. Really like the over all design of the unit. Looks like draft air comes in under the ash pan. Not convinced that part of the design will pre-heat the draft air enough to cause the exhaust gasses to burn effectively. My understanding is that a normal house thermostat is used to determine whether the distribution blower operates at 500 cfm or 1500 cfm. Seems like on warmer days (mid 40s) it might still be easy to get the house too hot if the fire is going. Don't care for the small cast iron grate with no shaker. Seems like getting the ashes down into the pan would be a pain in the rear. The most expensive option I've found so far.

Does anyone else have any suggestions, or any feed back on the unit I've listed? At this point, I want to talk to the folks at FireChief and Kuuma, but I want to learn more before proceeding with either one of them. The Kuuma is likely built much better, but I suspect that the FireChief is similar to build quality to what I am using now, maybe a little more efficient. My current unit has lasted 40 years, so I'd question paying an extra $4,300 for the Kuuma unless there are other good reasons to do so.

Thanks!
Mark

 

[NSMaple1]

Drolet Heat Commander.

 

[Woodchuck71]

Using the energy king, bought it in 2010 to replace a Bryant.
I can't use the boiler type because of the water, and like the forced air better.
Like it better than the Bryant.Uses secondary air.
No idea how much I burn,I'd guess around 5/6 cord?
Pretty much runs from November until March or so.
Ducted into the HVAC, clean the furnace every spring, replaced fire brick this year.
Sitting in the attached garage,keeps the garage around 65°when it's in the teens outside, house around 75° give or take.
All together around 3000 sqf, 2×6 construction

 

[moresnow]

Drolet Heat Commander.

Look at this for sure. Great ongoing review on another site right now.

@brenndatomu opinion requested

 

[brenndatomu]

Shelter - Based on the reviews, appears to be junk.

Fire Chief - Looks like it only uses 6 fire bricks, and they lay on the bottom where they are likely to be broken while adding wood. Forced draft which I have mixed emotions about. Supposed to have a secondary burn chamber, but I don't see how they are pre-heating the draft air. Need to understand how they are trying to do this before I'd be willing to go this route. Also one of the cheapest models.

Same furnace...and yes, absolutely 100% junk. (post 2017 models)

The Kuuma is likely built much better, but I suspect that the FireChief is similar to build quality to what I am using now, maybe a little more efficient. My current unit has lasted 40 years,

Some people aren't even getting a full season out of them before they are warped and cracked...not to mention all the backpuffing into the house! All this, and many people are still cold to boot!

So far, I'm looking at the USSC Hotblast, Kuuma Vapor Fire, Royall/Energyking, Fire Chief, and Shelter.

Kuuma VF100, Drolet Heat Commander, and the Shelter/Fire Chief are the only models available now...and obviously there are really only 2 real choices there.

Kuuma Vapor-Fire - Seems to have a strong customer base. Really like the over all design of the unit. Looks like draft air comes in under the ash pan. Not convinced that part of the design will pre-heat the draft air enough to cause the exhaust gasses to burn effectively. My understanding is that a normal house thermostat is used to determine whether the distribution blower operates at 500 cfm or 1500 cfm. Seems like on warmer days (mid 40s) it might still be easy to get the house too hot if the fire is going. Don't care for the small cast iron grate with no shaker. Seems like getting the ashes down into the pan would be a pain in the rear. The most expensive option I've found so far.

You need not worry about the Kuuma burning dirty...just doesn't happen...cleanest burning forced air wood furnace that there is...Mr Lamppa claims to have never cleaned his chimney, ever, annual inspection only.
Overheating the house is not an issue either...blower runs on low 99% of the time...heck, I don't even have the Tstat hooked up on mine...simply adjust computer to heat level desired (I'm on low 99% of the time) and load the appropriate amount of wood (same as an other wood burner) for the days weather. Low supposedly burns 3-4 lbs of wood per hour...medium 5-7, high 8-9...L/M/H is infinitely adjustable, so that's why the range is given.
No shaker grate needed, the Kuuma will burn down to a small pile of fine ash, it is easily pulled to/through the grate with the included tool. Reloading is a 3 minute process, then close the door and walk away...it really is that easy...these things are kinda boring to run honestly.
The Kuuma has well earned its title as the king of wood furnaces...now as was mentioned, Drolet has just released the Heat Commander, which is based on a long proven firebox/heat exchanger design, but has now been updated with computer controls...early reports from users are positive...I would not hesitate to own one of these units, other than they are a first year new model at this point...that said, Drolet has a reputation for taking care of their customers...as far as I know, they replaced or refunded everybody that had cracking issues with the first gen Drolet Tundra/Heatmax...the later Tundra/Heatmax II did not have these issues.
Look at what the different models are designed for, as far as life span...Kuuma is warranted for 25 years...said to be built for 30-40 year life.
Read the warranty on the Drolet carefully...mostly warranted for 5 years or less...the "lifetime" warranty actually covers very little...very little.
If you can afford the Kuuma, that is the hands down choice...and they have unparalleled customer service too...bottom line, buy once, cry once...a couple years down the road, you will be glad you did it.
The only, and mean ONLY, people you ever hear of (and its only been a couple/three that I know of)) that are not happy with their new Kuumas are people with huge leaky house that have a MONSTER heat load...too much for a 4.1 CF furnace to keep up with. They are rated up to 3500 sq ft, and people with well insulated homes larger than that have great success with the VF100 too.
We heat an average insulated 1940 cape cod style home, ~2000 ft living area and 1200 basement, easily with the VF100...it just plays with it...this is the 3rd season with it and I have had the computer off low twice...once each in the last two winters, not at all yet this year...house is generally 70-73.

 

[fields_mj]

Same furnace...and yes, absolutely 100% junk. (post 2017 models)

Some people aren't even getting a full season out of them before they are warped and cracked...not to mention all the backpuffing into the house! All this, and many people are still cold to boot!

Kuuma VF100, Drolet Heat Commander, and the Shelter/Fire Chief are the only models available now...and obviously there are really only 2 real choices there.

You need not worry about the Kuuma burning dirty...just doesn't happen...cleanest burning forced air wood furnace that there is...Mr Lamppa claims to have never cleaned his chimney, ever, annual inspection only.
Overheating the house is not an issue either...blower runs on low 99% of the time...heck, I don't even have the Tstat hooked up on mine...simply adjust computer to heat level desired (I'm on low 99% of the time) and load the appropriate amount of wood (same as an other wood burner) for the days weather. Low supposedly burns 3-4 lbs of wood per hour...medium 5-7, high 8-9...L/M/H is infinitely adjustable, so that's why the range is given.
No shaker grate needed, the Kuuma will burn down to a small pile of fine ash, it is easily pulled to/through the grate with the included tool. Reloading is a 3 minute process, then close the door and walk away...it really is that easy...these things are kinda boring to run honestly.
The Kuuma has well earned its title as the king of wood furnaces...now as was mentioned, Drolet has just released the Heat Commander, which is based on a long proven firebox/heat exchanger design, but has now been updated with computer controls...early reports from users are positive...I would not hesitate to own one of these units, other than they are a first year new model at this point...that said, Drolet has a reputation for taking care of their customers...as far as I know, they replaced or refunded everybody that had cracking issues with the first gen Drolet Tundra/Heatmax...the later Tundra/Heatmax II did not have these issues.
Look at what the different models are designed for, as far as life span...Kuuma is warranted for 25 years...said to be built for 30-40 year life.
Read the warranty on the Drolet carefully...mostly warranted for 5 years or less...the "lifetime" warranty actually covers very little...very little.
If you can afford the Kuuma, that is the hands down choice...and they have unparalleled customer service too...bottom line, buy once, cry once...a couple years down the road, you will be glad you did it.
The only, and mean ONLY, people you ever hear of (and its only been a couple/three that I know of)) that are not happy with their new Kuumas are people with huge leaky house that have a MONSTER heat load...too much for a 4.1 CF furnace to keep up with. They are rated up to 3500 sq ft, and people with well insulated homes larger than that have great success with the VF100 too.
We heat an average insulated 1940 cape cod style home, ~2000 ft living area and 1200 basement, easily with the VF100...it just plays with it...this is the 3rd season with it and I have had the computer off low twice...once each in the last two winters, not at all yet this year...house is generally 70-73.

I see your signature lists a LOT of wood burners. Have you tried them all and only kept the Kumma, or is it just a list of what you've looked into? Many years ago, I was looking into a Yukon several years ago, but I never pulled the trigger. If you've used one, or know someone who has, I'd be interested in hearing their thoughts/opinion of the unit just for curiosity sake.

The more research I've done on the specific options available, the more I agree with your assessment. I will say, however, that there are some companies are still offering coal fired furnaces that are exactly the same as the units that I looked at several years ago. I have no plans of going that route, I'm just pointing out that some are still available.

I had originally planed on replacing my unit over the summer. At this point, I will likely limp it along for one or two more years to see how the Drolet does. I'm leaning towards the Kumma pretty heavy. The price tag is a little scary considering the Drolet is less than half that, but the build quality, customer service, and the overall serviceability of the design would be enough to justify the cost.

Thanks,
Mark

 

[brenndatomu]

Have you tried them all and only kept the Kumma

Yes...heck, that isn't even a complete list! (Edit: updated) If I were hard up for money and had to go back to a (modded: think DIY Heat Commander) Tundra, I would be OK with that...plan on sticking with the Kuuma though!
The Yukon(s) were capable of huge BTU's, but a dirty burner...that's what ultimately got them sent down the road...tired of plugged heat exchangers and chimney mid season...and the Husky was about due for a $700 heat exchanger replacement too.
Coal burners make poor wood burners...a proper wood burner, like the Kuuma, will spoil you! You don't know what you don't know, until you know it...you know?!
Just a little note as to the cost of a Kuuma...all the hardware and exposed metal inside the firebox is stainless...quality costs more.
Feel free to call Lamppa and talk with them...I think you will like what you hear...and they will still take your call after the sale too...heck, sometimes you end up on the phone with Mr Lamppa himself...although that is probably increasingly rare since they have gotten VERY busy in the last year.

 

[fields_mj]

Coal burners make poor wood burners...a proper wood burner, like the Kuuma, will spoil you! You don't know what you don't know, until you know it...you know?!

I know, right?

Just a little note as to the cost of a Kuuma...all the hardware and exposed metal inside the firebox is stainless...quality costs more.

That is one thing that I am keeping in the back of my mind. I don't know anything about the Drolet as far as build materials. Their video's really don't show much on that, but the Kumma videos show everything. It's clear that the thing is not only built like a tank, but that they took the high road on material selection as well, and that really does increase the cost significantly.

 

[brenndatomu]

I had originally planed on replacing my unit over the summer. At this point, I will likely limp it along for one or two more years to see how the Drolet does.

If you are thinking Kuuma at all, now is the time...material costs keep rising, and for 2021 there is now a 26% tax credit on clean burn heaters...including installation costs too!
http://www.timberjay.com/stories/lamppa-stoves-now-more-affordable,17203

 

[JRHAWK9]

Hi Bren

Wow, never thought I'd see a Kuuma coming up on this site. I always thought this forum was mainly for all the dirty burners and for those who prefer to "dispose" of their used tires in them.

Kuuma owner here as well since late 2014. I second everything Bren said above.

 

[aokpops]

I bought the Drolet Tundra in 2014 . Had a shelters 2626 before the drolet used the Shelters about 2 years came home from work on a Friday with the chimney on fire was lucky and got it out before any damage . My wood is seasoned most is 10 years old. I used a foxfire I bought used for 150.00 in about 1994 used it for about 20 years an never had a fire issue clean the chimney once a year an done . That night after the fire I knew the Shelters was gone but wood heat was all I had . Menard had a big sale on the Drolet only till Saturday the next day . To convenience your wife we need a new wood furnace in less than 2 years is hard . After buying the Drolet my back said .Thank You ! The burn time went way up was using almost half the wood . Put a glass door on the Kumma and I.m buying it .