Vapor Fire 100 Measurement Question

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Blue Man

New Member
Sep 6, 2021
5
Warren, ME
Hi everyone, I'm the proud soon-to-be owner of a VF100 (ordered last week, expect delivery sometime in mid-October (hopefully). I'm replacing a 1991 ThermoPride hot air furnace that has been occasionally heating a 2300 square foot two-story farmhouse in coastal Maine when we don't have our Hearthstone Mansfield stove or LG heat pump filling in the gaps. I've been researching for weeks here (thank you all for the great info and reviews) and even called Dale at Lamppa with a couple of installation questions. But I thought it would be good to introduce myself here and ask about a few other things so as not to needle Dale too much. So, here they are:

1) Does anyone have the exact measurement for the return opening on the blower box? I'd like to build my box before the furnace arrives but I can't find the measurements anywhere. I know the box itself measures 22" x 26", but in some pictures it looks like there's a smaller opening. Should I just build it to mate with the full size?

2) My existing Supply plenum is 21" x 21" and I think I'd like to buy a pre-made transition box (I think they're usually set up for evaporator coils, which I don't have - no central AC here) to fit the VF's 24" x 24" bonnet opening. I know I could build/buy a new plenum, but if I can save myself the hassle I'd like to.

3) I have 4 cords of 18" to 20" white oak seasoning under cover since Spring of 2018 and the mc is around 18%. My basement is full size with a field stone foundation, some insulation, and a concrete floor. I have a full bulkhead with concrete steps but it would be much more convenient to chute it down through a casement window closer to the woodpile. My concern is with insects. How much wood do people generally keep on hand in their basement? A week? A month?

4) I've never had draft problems with my Hearthstone (on a separate chimney, of course!), but is this a problem with the VF? It will be connected to a stainless-lined brick chimney 37' from base to cap. Should I get a manometer before hook up or wait to see?

Thanks again for all your help and time. I've enjoyed reading through the posts and will get pics up as soon as everything's up and running.
 
1) Does anyone have the exact measurement for the return opening on the blower box? I'd like to build my box before the furnace arrives but I can't find the measurements anywhere. I know the box itself measures 22" x 26", but in some pictures it looks like there's a smaller opening. Should I just build it to mate with the full size?
There is a lip on the blower box to connect the duct...I don't recall the exact size at the moment, I can get the measurement later today if someone doesn't get it for you before.
2) My existing Supply plenum is 21" x 21" and I think I'd like to buy a pre-made transition box (I think they're usually set up for evaporator coils, which I don't have - no central AC here) to fit the VF's 24" x 24" bonnet opening. I know I could build/buy a new plenum, but if I can save myself the hassle I'd like to.
What I've done before was just make an adapter...just a piece of duct sheet metal cut to 26" x 26" and then a 1" lip bent down the whole way around...then a 19" x 19" hole can be cut in the middle (once you know for sure if you need it to be right in the center, or if it needs to be offset to one side or the other to make the furnace/pipes/ducts all line up correctly. Once the hole is cut a 1" lip can be bent up the whole way around...your existing plenum will drop on to that then. I literally hung my plenum from the ceiling and then scooched the furnace under it.
3) I have 4 cords of 18" to 20" white oak seasoning under cover since Spring of 2018 and the mc is around 18%. My basement is full size with a field stone foundation, some insulation, and a concrete floor. I have a full bulkhead with concrete steps but it would be much more convenient to chute it down through a casement window closer to the woodpile. My concern is with insects. How much wood do people generally keep on hand in their basement? A week? A month?
I tried a couple weeks worth once...first and last time...the bugs came out in droves once they warmed up.
4) I've never had draft problems with my Hearthstone (on a separate chimney, of course!), but is this a problem with the VF? It will be connected to a stainless-lined brick chimney 37' from base to cap. Should I get a manometer before hook up or wait to see?
You WILL want a manometer....a simple Dwyer Mark II model 25 works fine...they can be bought lightly used or often even NOS on ebay for $25-35. With a chimney that tall you very well may need more than just the Fields baometric damper that Lamppa sends with the VF to control the draft...talk to them about it, they have dealt with tall chimneys before.
 
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There is a lip on the blower box to connect the duct...I don't recall the exact size at the moment, I can get the measurement later today if someone doesn't get it for you before.

What I've done before was just make an adapter...just a piece of duct sheet metal cut to 26" x 26" and then a 1" lip bent down the whole way around...then a 19" x 19" hole can be cut in the middle (once you know for sure if you need it to be right in the center, or if it needs to be offset to one side or the other to make the furnace/pipes/ducts all like up correctly. Once the hole is cut a 1" lip can be bent up the whole way around...your existing plenum will drop on to that then. I literally hung my plenum from the ceiling and then scooched the furnace under it.

I tried a couple weeks worth once...first and last time...the bugs came out in droves once they warmed up.

You WILL want a manometer....a simple Dwyer Mark II model 25 works fine...they can be bought lightly used or often even NOS on ebay for $25-35. With a chimney that tall you very well may need more than just the Fields baometric damper that Lamppa sends with the VF to control the draft...talk to them about it, they have dealt with tall chimneys before.
Ah, thank you. The 26" x 26" adapter is a great idea (and much cheaper than the transition duct). I emailed Dale re: the damper.
 
I know the box itself measures 22" x 26", but in some pictures it looks like there's a smaller opening. Should I just build it to mate with the full size?
The return duct connection is 22" x 26"...the box itself is 24" wide x 28" tall (its actually taller if you include the base too)
 
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Well over a month's worth of wood in my basement for the coldest part of burn season. Notta bug issue whatsoever. Very well seasoned and almost completely without bark seams to work fine.
 
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Well over a month's worth of wood in my basement for the coldest part of burn season. Notta bug issue whatsoever. Very well seasoned and almost completely without bark seams to work fine.

First floor burner here, we bring zero wood in ahead of time. Ice cold wood gets loaded and works great. I have a small hoop under a carport roof that holds about a week’s supply outside.
 
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My dad puts the entire amount he burns for the season in his basement. It's in a back corner that's part of his 25% unfinished. He never has many issues with bugs, and he's been doing it like this since I can remember.
 
When I moved here 43 years ago it took 10 cords to heat this old farmhouse
Now I use just under 4. In all thoughts years, the basement has held every stick of wood
with never a bug problem as long as your wood is seasoned below 20% MC and your
basement is dry
 
When I moved here 43 years ago it took 10 cords to heat this old farmhouse
Now I use just under 4. In all thoughts years, the basement has held every stick of wood
with never a bug problem as long as your wood is seasoned below 20% MC and your
basement is dry
Must be a regional, or type of wood thing then, because my basement is dry, and so is the wood, bugs were stinkin everywhere! One rack lasted me about 2 weeks, and that was the last one that ever came in the basement! I have no issue walking 30' out to the attached garage to get the wood...garage is not heated so the bugs don't wake up, until its too late :ZZZ ::-)
 
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Must be a regional, or type of wood thing then, because my basement is dry, and so is the wood, bugs were stinkin everywhere! One rack lasted me about 2 weeks, and that was the last one that ever came in the basement! I have no issue walking 30' out to the attached garage to get the wood...garage is not heated so the bugs don't wake up, until its too late :ZZZ ::-)

So you don't keep any wood at all downstairs? I pretty much keep a max of two of my carts worth at a time (~1,000 - 1,200 lbs worth). One cart's worth in the wood rack and one on deck. Once I empty the rack, I stack what's in the cart on the rack and then go re-load the cart and bring it inside to let the splits get up to temp.

I also have an oversized 8' long rack full of BL that has been sitting down there for a few years now. It was the last of my big BL splits that I decided to keep as my "emergency wood" just in case something happens where I can't bring in wood from the outside.
 
So you don't keep any wood at all downstairs?
Nope...not unless its a couple sticks that I just decided not to load at the last minute...or maybe one that was wet on the outside from melting snow or something...
 
I been wondering about this situation about the wood too..I do have a small wood shed and about one or two weeks ago I transferred "kiln dried oak wood 16 inches out of two cages and put in my wood shed to get them out of the house...Now it is raining and some snow today and I felt the top of the wood pile (about 1/4 of load in the back (facing I guess) and it felt dry but should I bring some into the house just to be ready or should maybe bring some inside the garage in the back to make sure it is dry..Its important now for we are going to use this wood on the 28th of Oct and more rain and snow might be coming with colder temperatures--what do you people suggest--should I bring in some and put on the back porch inside where the stove is? Or could I leave it in the wood shed.?
clancey

updated wood shed pictures 10-07-21 001.JPG
 
I'm not sure if their is any science behind it, but I read it's "better" to let the wood get up to inside ambient temp before loading. One of the reasons why I always have a load on deck...along with being able to keep the wood in very dry air and near the wood furnace for a bit to help it lose any surface moisture it may have.
 
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being able to keep the wood in very dry air and near the wood furnace for a bit to help it lose any surface moisture it may have.
Certainly doesn't hurt...especially if it got a little wet on the outside...course with my wood being CSS 4-5 years and Daryl claiming its "too dry"...maybe I should just throw it in wet... :eek: ;lol
 
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Certainly doesn't hurt...especially if it got a little wet on the outside...course with my wood being CSS 4-5 years and Daryl claiming its "too dry"...maybe I should just throw it in wet... :eek: ;lol
The stuff I burned towards the end of last winter and what I'll be burning all of this winter ('21-'22), all of next winter ('22-'23) and around half of the following winter ('23-'24) was all C/S/S in Spring of '15. So it will be 6.5 years this winter, 7.5 the next and 8.5 the next. LOL

This is assuming I don't sell any. I have had an ad up for awhile. Somebody contacted me about possibly buying 1-2 cord in November. He's just moving to the area and said he's having a hard time finding people selling truly seasoned wood. Told him he doesn't have to look any further. Although I have it priced high.
 
Thanks just to be on the up and up with this first burn I think that I will bring in a few pieces just to have room temperature to it and that sounds logical to me---lol lol...Don't want my installer to have too hard of a time to light the stuff--lol...Me I could keep it outside for all eternity hoping it will be fine when it has to be used.. I also have a wood moisture tester and a stove pipe temperature gauge coming and a nice tribit for my water pot..--getting ready for this motion in my life---lol--thanks everyone...clancey.
 
I bring one 330 gallon tote ( approx 1/3 cord ) full of wood into the basement at a time. I've had a couple issues with bugs but not enough to change my system. Only touching a piece of wood one time after it leaves my splitter is nice. :)
 
Thanks and that's what I am going to do and I at first had it in two cages on the back porch but decided I did not need that much inside at a time but now I will bring some inside especially with the weather coming...--just to know that it is is nice and dry for my first burn...thanks..clancey
 
We bring in a cord or two at a time in our dungeon of our basement.
 
Thank you so much and started a new thread about this wood that I brought in asking if it is enough for the first stove lighting..thanks everyone and now to my own thread...This thread is about vapor fire 100 question....so off to my thread--clancey
 
When I first started burning wood I kept my winter supply in the attached walkout garage and would only keep 1 weeks worth in the basement at any time. For the past 5 winters I have put all my winters supply in the basement to free up much needed space in the garage. As of yet no problems with bugs. Any pieces that are a little punky or show the slightest signs of infestation (ants etc..) are stored outside, under cover, and go directly to the furnace when brought in.
 
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Hi all. I've had the VF running for about a week now. Installation was fairly smooth with the help of a few friends. I installed a Dwyer Mk II and my drafts are around .06-.08 with the damper weighted accordingly. I'm not sure what to do when it gets really cold out since it's only been as cold as the upper 20s so far. I also put in a four probe BBQ monitor and my temps are:

Stack: 350-450* range
Supply: 100-150* range
Return: 67-70* range
Ambient temp in basement: 67-72* range

I have three return air ducts connected. Two are from the main floor of the house and one is pulling off of the ceiling of the basement. I'm thinking of running the basement return to a box attached to the plenum (not through it, just attached and vented so the surface temp of the metal warms the air somewhat).

I've not filled the firebox to the top, mostly half or a little more. I'm using two year-old oak with a MC of about 22% on average.

I'm wondering if you guys have any suggestions for improvement. My two primary concerns are high stack temps due to over-drafting and how to raise the return air temp. Also, for those who installed a variable speed blower control, where did you buy it and how difficult is it to wire in? Would you recommend doing it now or should I wait a season and see how things perform once it gets colder?

I've attached screenshots of the temp ranges of the stack, supply, and return. Thanks everyone!
 

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First off, nice data!! Not too often people come on here with data like that. 👍

As far as your draft, ignore the setting on the BD. Set your draft to the Dwyer. I had to add washers (weight) to my BD in order to get it down to where I wanted it I'm currently running ~-0.04". I'd set it anywhere between -0.04" and -0.06". Once we get colder weather I tend to bump my draft up closer to the -0.06" area. Lowering your draft will pull down your stack temps. Also, the higher you have the computer set at, the higher your average stack temps will be.

Raising the return temp......I am pulling all my return air off the basement ceiling and also have a duct sucking in some of the radiant heat off the front face of the furnace. This gives me return air temps of between 78° to 84° when I have a fire going. I don't have my Kuuma return duct hooked into the main house return duct. I'm using an open staircase, which, for me, works terrific.

As far as wiring in a head pressure controller. It's not all that difficult to do. It made a big difference for me.

This is what I am using. There are other options that will work.

I have a very crude wiring diagram of how I originally wired mine up. I could PM to you if you want, but I won't be responsible for burning down your house. LOL One other forum member ( @garmford ) used it to get his wired up and I believe he's still using it to this day.
 
First off, nice data!! Not too often people come on here with data like that. 👍

As far as your draft, ignore the setting on the BD. Set your draft to the Dwyer. I had to add washers (weight) to my BD in order to get it down to where I wanted it I'm currently running ~-0.04". I'd set it anywhere between -0.04" and -0.06". Once we get colder weather I tend to bump my draft up closer to the -0.06" area. Lowering your draft will pull down your stack temps. Also, the higher you have the computer set at, the higher your average stack temps will be.

Raising the return temp......I am pulling all my return air off the basement ceiling and also have a duct sucking in some of the radiant heat off the front face of the furnace. This gives me return air temps of between 78° to 84° when I have a fire going. I don't have my Kuuma return duct hooked into the main house return duct. I'm using an open staircase, which, for me, works terrific.

As far as wiring in a head pressure controller. It's not all that difficult to do. It made a big difference for me.

This is what I am using. There are other options that will work.

I have a very crude wiring diagram of how I originally wired mine up. I could PM to you if you want, but I won't be responsible for burning down your house. LOL One other forum member ( @garmford ) used it to get his wired up and I believe he's still using it to this day.
Hey, thanks for the tips! I'd love that wiring diagram, and I'll send you an indemnity form LOL.