Kiuma VF 100 not heating my house! Disappointed!

[bropp]

For the last five years I've been reading great things about the Kuuma vf100 and have been wanting one. I finally purchased one and am very disappointed- I can't get it to heat my house! The firebox is a blast furnace but the plenum feels cool. I don't know why the heat won't leave the firebox. I can't get my house above 60 and its in the upper 50s in the morning and it's been super warm outside- lows 20 above and highs close to thirty! I have a thermometer on the registers and usually reads 72. I don't know how to get more heat from it. I insulated the plenum and put a probe in one foot above the plenum- when the furnace is roaring on the highest setting it reads 90 degrees.

I live in a 3000 sq ft house with two garage doors in the lower level. It is essentially a 1500 sq ft ranch with a Wood walled 2x6 walkout basement. The entire thing has r19 walls. The garage doors are insulated and plugged around the edges, I don't use them. House was built in 94 and has good insulation .
I've been burning wood my entire life. I am burning dry Ash and maple between 15-20 percent on the moisture meter.
6 inch class a chimney with barometric damper. I've tried every setting on the damper and just got a Dwyer mkii to check, but think its okay as i have flue temps between 200-250. Chimney goes through a thimble and is about 25 feet tall.
I made a duct system for it- not ideal but am moving it next year. Has 10x20 trunk with 4 8 in takeoffs. I've played all around with changing the static duct pressure to increase air temp. Cold air return comes from up stairs.

The air coming out just feels cold. I've talked with Dale about a dozen times and he's been very nice, but it hasn't gotten any warmer.
My wire is furious about this whole problem and wants it returned immediately. She grew up in an uninsulated farmhouse with a hot blast that was always 80 inside even when it's -35 outside. When I go there the plenum is always HOT when it calls for heat. Mine is cold.
Help! Is the Kumma actually as good as everyone says? I really regret buying it!
This has been going on for over two months
I've tried everything!

 

[Mustang71]

Do you have any control over air into the furnace with the kuuma? My englander puts out heat between 120 and 140 when its burning up to temp. The face temp is between 400 and 450 of the magnetic guage. The chimney temp is always 300 or higher on the magnetic gauge. I had your same issue when I got my englander but mine is all manual controls. If I dont have the fire roaring before I shut any air down then you get poor heat. These EPA furnaces are nothing like the pre EPA ones.

 

[homemade]

Does the blower on the kuuma switch from low to high?

 

[panolo]

I know @Ryan'smilling installed one and seemed to be happy with it. Maybe he has an idea or two.

 

[cantoo]

Disconnect the return air flex ductwork that you installed and physically see and feel if there is air moving. 90 degrees on top of a stove is nothing. Can you cut opening into the ductwork you installed on top and connected to your existing ductwork so you can see and feel what is happening? This guy has a series that might help you, I assume you could ask him questions too?

 

[panolo]

Same with @JRHAWK9 I think he has posted he's been using his for 5-6 seasons.

 

[homemade]

Jrhawk I think also weighs hus wood cause the thing over heats his house.

 

[bropp]

Do you have any control over air into the furnace with the kuuma? My englander puts out heat between 120 and 140 when its burning up to temp. The face temp is between 400 and 450 of the magnetic guage. The chimney temp is always 300 or higher on the magnetic gauge. I had your same issue when I got my englander but mine is all manual controls. If I dont have the fire roaring before I shut any air down then you get poor heat. These EPA furnaces are nothing like the pre EPA ones.

The Kumma automatically controls air. Fire is super hot! Thanks!

 

[bropp]

Disconnect the return air flex ductwork that you installed and physically see and feel if there is air moving. 90 degrees on top of a stove is nothing. Can you cut opening into the ductwork you installed on top and connected to your existing ductwork so you can see and feel what is happening? This guy has a series that might help you, I assume you could ask him questions too?

I have a lot of luke warm air coming out.
The blower is certainly pushing air through the furnace. It goes in 60 and comes out 90. By the time it reaches my bedroom it's mid 70s at best. I watched all the Kumma videos a dozen times and spoke with that guy too.

 

[bropp]

Does the blower on the kuuma switch from low to high?

If I have the thermostat on it only runs on high because the house won't get above 65, so lately I leave it on low

 

[Mustang71]

If it goes in 60 and comes out 90 something isn't right. It should come out way hotter than 90 if the fire is going like you say it is. My air comes out at 90 when the face temp is 200 degrees or when I'm just rolling on coals. Is it burning through the wood real quick? I know people on here get real long burn times with the kuuma.

 

[bropp]

If it goes in 60 and comes out 90 something isn't right. It should come out way hotter than 90 if the fire is going like you say it is. My air comes out at 90 when the face temp is 200 degrees or when I'm just rolling on coals. Is it burning through the wood real quick? I know people on here get real long burn times with the kuuma.

It will burn on high 8-10 hours the way it is now. The firebox temp won't register with my ir thermoter, over 1100 degrees, and feels like a lot over that. It will almost burn your hand when you open the door at full burn. The heat just doesn't leave the fireboc

 

[Mustang71]

I just loaded my englander. Face temp is 250 basement is 62 and output is 110. This is my 1100$ EPA furnace. Your furnace should be capable of way more. Does the manual say to install a baro damper on the stove pipe? I thought most EPA stoves didnt want those installed. That ductwork seems really big and so do 8 inch heat runs. When theres not enough restriction the heat flys past the heat exchanger so fast it doesnt pick up the heat. Also we try to never take heat runs off the end of the ductwork that destroys the back pressure.

 

[Ryan'smilling]

What's your barometric damper set at? There's a decent difference in how much heat it puts out at the minimum versus the maximum setting on the damper. I assume that if you talked to Dale, he had you move the low limit switch to the top of the plenum. Does your fan run constantly during the middle 80% of your burn time?

 

[Mustang71]

Alright I read the manual and they want a baro damper for some reason. Looking at your picture it looks like yours is not level? Like if it's on an angle pipe the tee is supposed to face sideways so it can sit level. The other thing I was wondering about is how tight your house is and if you need a make up air of some sort.

 

[NSMaple1]

Yes, baro install is incorrect. Also looks like you have a big imbalance in duct area between supply and return. A quick couple of fast takes.

 

[farmer steve]

It will burn on high 8-10 hours the way it is now. The firebox temp won't register with my ir thermoter, over 1100 degrees, and feels like a lot over that. It will almost burn your hand when you open the door at full burn. The heat just doesn't leave the fireboc

Listen to these guys. They have been burning for a while. They know what's yp.

 

[Marshy]

It will burn on high 8-10 hours the way it is now. The firebox temp won't register with my ir thermoter, over 1100 degrees, and feels like a lot over that. It will almost burn your hand when you open the door at full burn. The heat just doesn't leave the fireboc

There's no way it's over 1100F. It would be slight red to dull red visually. That would be nearly over fire conditions. I would venture a guess that the stove manufacture never wants 1100F degrees or higher...
Are you sure your fan is running the correct way? Did you remove the filter and try it? Is your fan large enough to move the air? Is it on the return side of the system? So many questions.

At this point I would personally throw in the towel and call a HVAC professional who was experience with indoor wood furnaces and ask them to come out and look it over. Have then check the flue draft and the duct flow/pressure. I'm thinking it's the surrounding system and not the furnace itself.

 

[cantoo]

Marshy is right. It's hardly ever the unit it's almost always the ducting, fan or draft.

 

[Mustang71]

Marshy is right. It's hardly ever the unit it's almost always the ducting, fan or draft.

I go back to what I said my 1100 dollar epa furnace keeps it warm in here after I figured out how to use it. For the cost of a kuuma it should do amazing things.