Kumma VF-100 Installation questions w/ Pics

[Mbeall]

Hello all, Ive found a local family who purchased a VF-100, used it twice and unfortunately the father of the family passed away. Remaining family members don't want to use wood for heat so they offered it to me for what I think is a good deal. My home is located in WV, built in 2022 approx. 1800 sq ft rancher with full walk out basement and 230 sq ft unfinished bonus room I intend to finish and heat above the garage. I have a Thimble hole that I put in when they poured the foundation. From my current heat pump to where the furnace will sit is approx 30 ft. I will also have an approx 28 ft chimney on the outside. My plan is to use triple wall stainless. My main question is in the connecting to my duct work. I will attach photos but both my return and feed lines for the central air run all the way to where my stove will go. I extended the return to the point where I plan to place the stove during construction ( first photo). both lines then run parallel down the main beam of the home. ( 2nd Photo). (3rd photo) is where the lines terminate, the return then goes above the feed line and over to where my stove will sit.
My main questions are what configuration do you suggest as I only want to have to do it once and don't have experience with anything other than stand alone wood stoves. I have a friend who does HVAC work and is willing to help me out but I would like to have a plan in place before moving the stove in and calling him over. I don't have an open stairwell to the basement and I would like to be able to also introduce hot air into the basement as future plans are to finish 3/4 of it.

Thanks for your time and help.

 

[brenndatomu]

Congrats on scoring a lightly used VF!
Use doublewall chimney, not triple...it is cheaper, and superior (and smaller)
Is your supply ductwork metal? It needs to be for wood heat...it kinda looks like flex duct in some of the pics...

 

[Mbeall]

the main lines are metal with bubble wrap insulation. The branch lines off the main line going to individual registers are flex duct.

 

[brenndatomu]

Where you will be tying in is at least 180 sq inches of area?
My only concern would be that there is a few registers near where you tie into the supply duct...with a long flat run like that I'd worry a little bit about heat not being able to adequately gravity flow during a power failure. And if there are registers nearby, then it may be a good idea to run metal duct from the trunk to them...I'd not want non metallic duct within at least 10-15' of the furnace...like I mentioned before, there is really supposed to be none on the supply side for solid fuel heaters.

 

[Mbeall]

Understood, I’ll have to see how much it would cost me in order to get metal lines ran to everything. Or at least everything on the stove side of the furnace. I’d prefer to do it now then try and change it down the road once half the basement is finished. I guess this was on oversight on my end when I had the system installed.
Is there a max horizontal run recommended for the vf? I condisdered running the supply off the vf down 20 ft or so closer to the heat pump unit in order to add a few registers in the basement and have it tied in closer to the center of the house for more even heat distribution The master br is on the opposite end of the house from where the stove will sit and tie in.

 

[brenndatomu]

Where is your chimney at? To me that determines where the VF needs to be more or less.
As far as the horizontal run, I'd say most houses are within the VF's capabilities, as long as the duct is big enough...in many houses the supply duct gets smaller on the other end, and if that's where you want to tie in, then it may be too small and will not flow well back to the other end.
As long as you have the duct sizing worked out, then once you get fired up all you need to do is to tweak the registers (duct dampers) so that the heat ends up where you want/need it...for example, often times people like their bedrooms cooler.

 

[mikieb]

All I can add is that you really only need to go with a double wall chimney. I know from my stove to my chimney I run a single wall black pipe and most days you can rest your hand on the single wall part when the stove is running.... It just doesn't get that hot coming out of the VF to warrant the expense of triple wall.

The other thing is, I would get the stove moved into the basement... look at that you are working with... The VF is a big wood furnace.... situate it near where the chimney is going and bite off your problems one at a time.... and work your way thru it.

 

[mikieb]

Also.... another thing to add... as to the heating the basement part you are asking about. Get you VF hooked up to heat the main living area before you worry about the basement.... when running the VF it may throw enough heat off the unit it's self to keep the basement warm.

I have 1250 sf in my basement without any venting. I keep a house fan blowing low on the door face of the VF while it is running and the whole basement is dry toasty warm all winter without even trying.

 

[brenndatomu]

It just doesn't get that hot coming out of the VF to warrant the expense of triple wall.

Doublewall chimney pipe is superior to triple wall for wood burners, and cheaper.
Single wall stove pipe (connector pipe) will work, but doublewall will draft better, and stay cleaner. (and all the doublewall I've ever seen is SS inside, so one n done...cheap steel singlewall only lasts a couple years for most people when the stove/furnace is in the basement)

 

[Micdrew]

Sounds like you have a similar set up as me, my chimney was already installed when I bought the house so I had to work with what I had. The gas furnace was centered in the house with main supply/returns running out either side of the plenum, I ran a dedicated supply about 25’ from my VF to my gas plenum so I could get equal heat distribution throughout the house. Yours looks like it’s the same set up, centered in the basement? I also installed a spring open power close damper on the top of the plenum so when the power goes out it will automatically open and dump the heat into the basement, since I have a very long supply run I get 0 gravity flow into the duct work. this only works when the power goes out it won’t work in the case of a blower failure so keep that in mind. Hope this helps. I should add that I’m pulling the return air from my basement. Cut some air vets into my basement door so we could keep it closed, Works just fine

 

[Mbeall]

Thanks for all the info. I’m going to see about the price of upgrading my flex vents into metal duct work. Would it be worth it to cut a few vents into my return line in the basement that I can open on the winter time only to help with keeping everything leveled out ?
Micdrew
Do you have a link to the spring loaded dump Havel you have set up and/or a photo of your set up ?

 

[Micdrew]

Thanks for all the info. I’m going to see about the price of upgrading my flex vents into metal duct work. Would it be worth it to cut a few vents into my return line in the basement that I can open on the winter time only to help with keeping everything leveled out ?
Micdrew
Do you have a link to the spring loaded dump Havel you have set up and/or a photo of your set up ?

Thanks for all the info. I’m going to see about the price of upgrading my flex vents into metal duct work. Would it be worth it to cut a few vents into my return line in the basement that I can open on the winter time only to help with keeping everything leveled out ?
Micdrew
Do you have a link to the spring loaded dump Havel you have set up and/or a photo of your set up ?

 

[mikieb]

Love the return air plenum. Looks good.