Wood furnace vs. pellet furnace

[brenndatomu]

The drawback of the kuma is very high price

You keep bringing up the Kuuma's price...yes, it is more than the Drolet's, but compared to some of the large CAT stoves you are comparing too...I think it is a pretty good value...a lot more steel (stainless internally)/more firebrick/much larger blower, computer...top notch personal customer service...$5300 (current sale price...I think) for a VF100 is a better deal than $4000 for a large wood stove IMO.
And so say that you can do a 30 hour burn on a CAT stove...that in a furnace application probably would not be enough BTU output to overcome duct losses...and even if it would be, "most" people probably average 4 cords a year to heat their whole house with the Kuuma...so if you could save, best case scenario, 25% firewood...I say big deal, most people can make a cord of wood in a few hours!

 

[JRHAWK9]

And so say you can do a 30 hour burn on a CAT stove...

....and cat stoves are just using the cat as a band-aide to cover up for incomplete combustion. Without the cat cleaning up the leftovers, those things would smoke like crazy.

 

[JohnDolz]

Pound for pound propane has almost 4x the BTUs of pellets. @$1.21 a gallon it is considerably cheaper especially when you figure a 95%+ efficiency with the furnace.

I would look at the draft of the furnace or your house is too sealed up to give it enough air. The hotblast is a super simple stove to run.

What I learned (unfortunately after my plumber installed a high efficiency Condensing boiler) is that the boiler cannot condense unless return temp is 130 degrees or lower - I would bet that at least 95% of all high efficiency condensing boilers installed in the US rarely if ever run at that high efficiency rating. When I talked to the manufacturer of mine (I primarily use a wood boiler with storage but was trying to dial in the backup as we were going to be away for a bit) to solve a short cycling concern they had me tweak the settings on my Outdoor reset - when I complained that with their curve the boiler would never condense, the answer was "when it is over 60 degrees out it will condense like crazy".......................

 

[Medic21]

What I learned (unfortunately after my plumber installed a high efficiency Condensing boiler) is that the boiler cannot condense unless return temp is 130 degrees or lower - I would bet that at least 95% of all high efficiency condensing boilers installed in the US rarely if ever run at that high efficiency rating. When I talked to the manufacturer of mine (I primarily use a wood boiler with storage but was trying to dial in the backup as we were going to be away for a bit) to solve a short cycling concern they had me tweak the settings on my Outdoor reset - when I complained that with their curve the boiler would never condense, the answer was "when it is over 60 degrees out it will condense like crazy".......................

If you pay to have one installed I’d expect the installer to set it up right.

when I install the baseboard heat in the house in a couple of years I plan on installing a modulating boiler as back up to the Crown Royal.

 

[JohnDolz]

If you pay to have one installed I’d expect the installer to set it up right.

when I install the baseboard heat in the house in a couple of years I plan on installing a modulating boiler as back up to the Crown Royal.

I would recommend doing some research. There is a difference between a modulating boiler and a Modulating/Condensing boiler. Not sure of the efficiency rating on just modulating, high efficiency is usually tied to Condensing. Based on what I know (and that ain't much), you will have 2 challenges with a Mod/Con: 1. if you use outdoor reset to get water temperatures that are low enough to get the boiler to condense you are going to have a short cycling issue. 2. Most likely you will almost never have return temps that are low enough to have the boiler condense (think paying for a car designed to drive 200 mph but never being able to get above 30 mph). Based on what I know I would never pay the premium for a Mod/Con boiler given my given emitter setup. Disclaimer: since my propane hardly ever fires I did not put much energy into trying to resolve the issue ( i.e. I could actually heat my 1000 gallons of thermal storage avoiding the short cycling, etc).

"If you pay to have one installed I’d expect the installer to set it up right." One could "assume" that - not sure if you are old enough to recall the Odd Couple "Assume" episode, if not Google it. I challenged the manufacturer saying that I believed at least 80% of all of their boilers were installed incorrectly, he agreed. I asked him to contact my plumber and inform him of what was happening, he said "no". Translation: Your plumber sells my stuff which is really all I care about. If I call him and tell him that he does not know what he is doing he is going to stop selling my stuff and sell someone else's stuff instead.........

Edit: haven't thought about this in a few years, I should add that my boiler is just too big to modulate down low enough to avoid the short cycling. I am not sure if a smaller unit would be able to modulate down far enough but then again for it be big enough to meet my needs when it was really cold? I guess I am now educated enough to know what questions I should have asked.

 

[Medic21]

I would recommend doing some research. There is a difference between a modulating boiler and a Modulating/Condensing boiler. Not sure of the efficiency rating on just modulating, high efficiency is usually tied to Condensing. Based on what I know (and that ain't much), you will have 2 challenges with a Mod/Con: 1. if you use outdoor reset to get water temperatures that are low enough to get the boiler to condense you are going to have a short cycling issue. 2. Most likely you will almost never have return temps that are low enough to have the boiler condense (think paying for a car designed to drive 200 mph but never being able to get above 30 mph). Based on what I know I would never pay the premium for a Mod/Con boiler given my given emitter setup. Disclaimer: since my propane hardly ever fires I did not put much energy into trying to resolve the issue ( i.e. I could actually heat my 1000 gallons of thermal storage avoiding the short cycling, etc).

"If you pay to have one installed I’d expect the installer to set it up right." One could "assume" that - not sure if you are old enough to recall the Odd Couple "Assume" episode, if not Google it. I challenged the manufacturer saying that I believed at least 80% of all of their boilers were installed incorrectly, he agreed. I asked him to contact my plumber and inform him of what was happening, he said "no". Translation: Your plumber sells my stuff which is really all I care about. If I call him and tell him that he does not know what he is doing he is going to stop selling my stuff and sell someone else's stuff instead.........

Simple tie in with a plate exchanger and a mixing valve to lower the outdoor boiler temps to the set point of the indoor boiler. The system runs at 120 degrees.

 

[JohnDolz]

Simple tie in with a plate exchanger and a mixing valve to lower the outdoor boiler temps to the set point of the indoor boiler. The system runs at 120 degrees.

Like I said, I don't know much and haven't given it any thought. I waste all my extra $'s chasing wood heating nirvana.

 

[Highbeam]

You keep bringing up the Kuuma's price...yes, it is more than the Drolet's, but compared to some of the large CAT stoves you are comparing too...I think it is a pretty good value...a lot more steel (stainless internally)/more firebrick/much larger blower, computer...top notch personal customer service...$5300 (current sale price...I think) for a VF100 is a better deal than $4000 for a large wood stove IMO.
And so say that you can do a 30 hour burn on a CAT stove...that in a furnace application probably would not be enough BTU output to overcome duct losses...and even if it would be, "most" people probably average 4 cords a year to heat their whole house with the Kuuma...so if you could save, best case scenario, 25% firewood...I say big deal, most people can make a cord of wood in a few hours!

Of course I “keep” bringing up the kuma’s price with each new poster asking about furnaces. It’s a very important aspect and when the rest of the competition is half as much (approximately) money this becomes a major factor. You might get tired of hearing it but that makes this fact no less valuable to newcomers.

There are plenty of positive reviews of the kuma that you don’t need to try and hide this one drawback. Be honest. It’s extremely expensive but for that you get x,y, and z.

And no window! Though the OP is putting this in a small furnace room it is still nice to see the fire during ignition.

 

[brenndatomu]

There are plenty of positive reviews of the kuma that you don’t need to try and hide this one drawback.

Not trying to hide anything...price is posted right there on their website...my point was you were playing up CAT stoves, and was just saying that I think the Kuuma is more bang for the buck

 

[maple1]

am I going to have a problem with running my heat duct downward from the furnace?

I don't have a wood furnace (have a boiler), but if I was to put one in I think I would 100% want the wood furnace supply ducting going up off the furnace - would be a primary system design constraint. Not even sure going down is manufacture recommended?

From a quick thread read, thinking most of your issue is due to the make/model of furnace. I would only go with Tundra, Caddy or Kuuma. Not sure from the read your complete system design & how the primary ducting setup is configured & the two furnaces tied together - could possibly be some issues there as well, or some may arise if you try to plumb another furnace in.

As far as fuels, I would pick my preferred fuel supply first, then furnace & design. Around here, pellets are one of the most expensive fuels. I would still be ahead of them if I had to buy all my wood already fully processed.

 

[Medic21]

I missed that. There is no way that you should take a stove like the hotblast and run the ductwork down. If you have a power outage it will overheat. The directions will tell you this and your insurance will not like it.

 

[andym]

Setting up a wood furnace to send heat downward will work, you will just need to install an automatic emergency heat dump. I would also install some kind of battery backup system as well. The heat dump will provide overheat protection in the event of power failure (or blower), but battery backup will allow you to operate as normal for a couple hours.

I am also a bit unclear as to how your current system is operating. I can't tell you the exact tie in method.

Is Digger79 still on this forum? Didn't he have a tundra1 set up in a garage supplting heat through the crawlspace?

 

[brenndatomu]

Not even sure going down is manufacture recommended?

It's definitely not...but as has been mentioned, emergency heat dump gets around that...BUT, the last manufacturer of those that I am aware of is no longer supplying them...you could make one as someone here did...just need a steel box with a large hinged door (1'x1') held shut by a spring attached to a 200* fusible link...box is mounted on the supply plenum with the door tilted down just enough so that it will fall open if the link melts.
Someone here made their own, don't recall who it was...modified a steel electrical controls box, bought the links from Grainger IIRC.

 

[brenndatomu]

Digger79 still on this forum? Didn't he have a tundra1 set up in a garage supplting heat through the crawlspace?

Yeah it was him ...haven't heard from him in a long time...I think he moved...maybe not using wood heat anymore...I dunno...

 

[Erichomeowner]

Setting up a wood furnace to send heat downward will work, you will just need to install an automatic emergency heat dump. I would also install some kind of battery backup system as well. The heat dump will provide overheat protection in the event of power failure (or blower), but battery backup will allow you to operate as normal for a couple hours.

I am also a bit unclear as to how your current system is operating. I can't tell you the exact tie in method.

Is Digger79 still on this forum? Didn't he have a tundra1 set up in a garage supplting heat through the crawlspace?

I have my furnace hooked up to a generator as well as my well pump and a few outlets so incase of power outage the gen will kick on. There is no other way I could direct the heat cause I need to down and into crawl space

 

[brenndatomu]

I have my furnace hooked up to a generator as well as my well pump

Auto start genny?

 

[Erichomeowner]

Auto start genny?

yes

 

[Medic21]

I have my furnace hooked up to a generator as well as my well pump and a few outlets so incase of power outage the gen will kick on. There is no other way I could direct the heat cause I need to down and into crawl space

Check with homeowners insurance. Mine said they would drop me with it in the garage or down draft.

 

[Erichomeowner]

Check with homeowners insurance. Mine said they would drop me with it in the garage or down draft.

insurance company is fine with it in garage. My concern is can I or am I able to to install a add on wood furnace and or pellet furnace with the way I need to connect duct

 

[brenndatomu]

yes

That's good...me personally, I would still do a Emerg. heat dump...I like a backup for the backup when it comes to fire inside my home...there are a thousand reasons that backup genny could fail...or the blower motor/controls could kaputz...EHD is pretty darn simple...I installed one even though my ducts will gravity flow, just for peace of mind...I could just see some numbnutz crashing into a pole and taking the power out right after I put a big load in and head off to work...and often times my family is still sleeping after I leave.
The risk of things over heating with a Kuuma are much less than with the old Yukon furnace I had, but if the power went out right after a large load of wood was put in and it was brought up to temp, things would still get pretty toasty with no blower taking the heat away (if it happened right as the furnace went into pilot burn...that can last quite a while sometimes)

 

[brenndatomu]

My concern is can I or am I able to to install a add on wood furnace

You would probably want to check with Lamppa first, but I'm betting that they would have no problem approving that install with a EHD in place...or need to check with whatever manufacturer you go with (your HO ins too)...Lamppa seems to be more willing to think outside the box on individual installs than other manufactures I've dealt with.

 

[JRHAWK9]

Safety Heat Dump

Automatic safety heat dump used for safe wood burning in wood furnace.

store.yukon-eagle.com

 

[Erichomeowner]

Safety Heat Dump

Automatic safety heat dump used for safe wood burning in wood furnace.

store.yukon-eagle.com

So do you install that on top or your plenum directly above the furnace?

 

[brenndatomu]

Safety Heat Dump

Automatic safety heat dump used for safe wood burning in wood furnace.

store.yukon-eagle.com

When you call them to order, they are out of stock, with no ETA...I think they are gonna end up shutting down.

 

[brenndatomu]

So do you install that on top or your plenum directly above the furnace?

I goes on the side of the plenum...