Need Suggestions on a New Wood Furnace Installation

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.
Status
Not open for further replies.

boatboy63

Member
Feb 6, 2010
205
Northeastern TN
Hi everyone. My first post but surely won't be my last. Been lurking around here reading for the last week or so and learning more than I ever dreamed.

We live in a farm house that was built in the 1890's. The 1st floor is roughly 1800 square feet and the upstairs is around 1400. Wife inherited the house in 2000 and we put in a 5 ton 12 SEER heat pump in the same year to replace a 30 yr old oil furnace. At the time she inherited it, it only had the lower level and we built the upstairs on about a year later. When we built the upstairs, we framed it out of 2x6's and put in R19 insulation. The lower level had very little insulation, as it had not been invented at the time the house was built. About 25% of the lower level walls were insulated by her dad, and that was only because of rooms he had added onto. I am proud to say it is framed out of oak sawmill 2x4's (the good stuff).

We have had an original Buckstove insert (28000 I think) that we have used every year to heat the front half of the house during the day. The stove burns everyday during the winter from around 9AM to 9PM to save on heating. After letting the stove shutdown at night, we always let the heat pump run to keep the back half of the house warm so we can sleep back there. After we first moved in, we would nearly freeze when we left the living room during the day due to lack of insulation all thru the lower level of the house. Over the past few years, we have added insulation to all exterior walls and it has helped, but is still nowhere close to airtight.

During the first week of December, the compressor locked up on our heat pump. I found it had a 10 year warranty and we still had 9 months remaining. I called a friend who does HVAC and he told me to check at a local supply house and see if it could be replaced under warranty. To my surprise, it was fully covered. I picked up the compressor and called the friend back to install. He said he was busy and would try to get up here some afternoon to change out compressors, pump it down, and then regas. I was scared to death of what my electric bill would be since we were now using the emergency electric strips in the furnace to heat with at night. Before I knew it, a month had passed and we got our electric bill. I was scared to open it as I knew it would be very high, since this December had been much colder than recent ones. Much to my surprise, my bill was less (KW/h) than the one a year ago. When we ran the heat pump and it was cold, it would nearly run all night. Most of the time, it would run for an hour or better, then the electric strips would kick in and within 10 minutes, it would be up to temp and shut off. About 10-15 minutes later, we would repeat the cycle. Since the heat pump has been out, the heat will run for about 10 minutes, shut off and not come back on for 20-30 minutes or sometimes longer. I should be getting my electric bill for January in the next few days, but am already considering not installing the new compressor and just selling the complete heat pump/furnace when spring gets here. Even though I have a couple of registers in the upstairs addition, the heat pump is primarily for downstairs only. I have a propane wall heater up there that seldom comes on due to the insulation. If you use the heat pump for A/C in the summer, the bill is very high. We quit using it and instead started using small window A/C's with digital thermostats in about 4 rooms. The bill is much cheaper that way.

Because of my eyes opening up to the heat pump vs. electric strip issue, I have been reading up on wood furnaces. I saw a Yukon Eagle wood furnace that uses propane as a back up and also to light the wood, should it go out. The only problem is it costs over $5000. I like the Englander 28-3500 wood furnace that is closer to $1000, but would like to have a built-in backup in the event we are gone for an extended time and the fire goes out. I have even considered building my own, as I understand the concept/principle and can weld. I looked into outside wood boilers, but don't really want to have to go outside to keep a fire going in all kinds of weather. The current ducting in the lower part of the house is galvanized 6" round duct and the air distribution is horrible as some rooms barely have any airflow and others will run you out. I would like to run new ducting and duct the furnace into it to distribute the heat.

The biggest problem I see is that the current location of my Buckstove/masonary chimney is at the end of the living room and is a good distance from the center of the house. Wife doesn't want to run stovepipe thru the upstairs area to vent the wood furnace. Because of this, I am considering tearing down the masonary chimney that is on an outside wall, putting the new furnace there, and installing the stainless triple wall pipe. We are basically a creosote breeding ground with the current setup. The only problem with trying to run new ducting is ground clearance. Where the furnace will be located, we have about 2 feet of crawlspace. On the back side of the house, there may be 10". I have thought about running the ducting under the house on the front half then running it up the wall where the current furnace is and ducting to the remainder thru the ceiling by installing a drop ceiling. My hearth is made out of concrete and I don't know how I can go about ducting from the top of the wood furnace thru the concrete hearth to get under the floor. I have thought about tearing out the hearth when the chimney comes out, but would still have to take the duct from the top of the furnace, over the side and under the floor. I can't install a drop ceiling in living room so I can't run ducting above the ceiling anyway and would have to go under the house.

Can someone please give me some suggestions on how to do this? Also, I appologize for the long post.
 
you will get a zillion suggestions but al l that aside you are doing a smart thing .do your research get the right furnace and you will never run that expensive heat pump and wake up to plenty of coals in the stove and a bed of glowing coals to easily relight for each charge.i have a englander 28-3500.for me the price and quality fit the bill and that large viewing window was a nice feature .i really like it for our needs ,we are never cold and usually have the windows open to vent the heat out
i burn around 6-7 cords a year and get 8-9 hour burns and it heats my 2,000 sq foot house no problem eve nat zero degrees outside ,there are easy DIY upgrades i have done that really helped in my application .keep in mind there are other good units out there too bu the cost goes up considerably ... if your able to muster up over 2 grand the caddy is a great option and epa certified so it will burn cleaner than most ...other super efficient furnaces in that category are the blazeking apex and the energy king.this year alone im on par to save $1,800 in fuel oil that i can now pocket free and clear and we never bought a drop of oil gas or propane 100% wood heat
my sister has a huge fancy heat pump unit they recently purchased it was like 5 grand and her bills to heat her home are usually over 500 bucks a month in the winter and for what? its not anything special her house is always way lower in temperature than mine, but then again we like it in mid to upper 70's
 
Care to explain your DIY upgrades you have done? Also, have you ever heard of anyone taking the heated output of the Englander, installing 2 90's on it and ducting it under the floor? I just didn't know how well it would work. I would probably have some sort of damper on top of the heat output so I could just dump it into the house at the furnace in the event of a power failure. I just want to design something that will work and keep ALL of the house warm, not just the front half of the house. BTW, I like the window on the Englander too. It gives wood burning more of a personality, if that makes any sense. Thanks.
 
honestly im not sure how well that idea o f yours would work ,im not much of a hvac guy .mine is tied into my ducting basically the outlet is 90out of the furnace and 3 feet later dumped into the plenum so it can be distributed ,i added more firebrick 6 to be exact (18 bucks) for more thermal mass then i added a second dayton blower (463cfm for 83$) and then a scrap sheet of stainless(10 bucks) above the baffle to keep baffle form possibly warping and add yet even more thermal mass on top of flames .added a flue damper for windy days or if i rippin fire id like to tame and stretch burn time out (10$ i rarely use this though)then i adjust the factory thermodisk to stay on until it hits 80 degrees internal temperature ,this keeps it going in the duct work and levels things out in the rooms better
 
I purchased a used Yukon dual fuel but never installed it. The fuel box was a little small for me, and it was a furnace and I decided a water boiler would be easier to integrate into my existing system.

If you can get a furnace to work with your other heater then you are money ahead. I would pass on the dual fuel, not worth the trouble, you already have a backup. If you are away then turn the heat down, just my two cents.

Finding and fixing all the vapor losses and adding insulation is a very good idea. Vapor loses can easily double your heat load.
 
I'm not a big fan of the all in one units. Too many things can go wrong, plus you may be efficient on one side, but its never both. From the way your talking about the ducting, you would need a downflow setup. Its something that you need to be careful with. You would probably need a heat dump like you said in case of an outage, and you need to follow ducting clearances to combustibles. You would need to insulate your ductwork also running it through an unheated area. Whats wrong with the masonary chimney? Depending on its condition, you could line it and insulate and it would be just fine. You should get a rough idea on how many btus you need to heat the home with. Also when doing the ductwork, it should be sized correctly. Otherwise you will still have hot cold spots in the house. Sounds like a large project. It won't be cheap. I agree with the air sealing and insulation.
 
sgschwend said:
I purchased a used Yukon dual fuel but never installed it. The fuel box was a little small for me, and it was a furnace and I decided a water boiler would be easier to integrate into my existing system.

If you can get a furnace to work with your other heater then you are money ahead. I would pass on the dual fuel, not worth the trouble, you already have a backup. If you are away then turn the heat down, just my two cents.

Finding and fixing all the vapor losses and adding insulation is a very good idea. Vapor loses can easily double your heat load.
I too was concerned with the size of the Yukon's firebox. I have read some reviews of it saying it had to be refilled every 4-6 hours and others saying it would last 12 or more. I just couldn't see how that something with such a small firebox could last as long as some claim.

As for insulation, we are doing what we can. When we built the upstairs additions on, we had enough trouble. We found there were no building "standards" in the 1890's. The 2x8 oak ceiling joists were anywhere from 14"- 20" on center. We ended up having to put 2x10's in for floor joists just to have enough clearance. We then had to "scab" some of them to try to have something to anchor to and actually have standards for centers so 3/4" OSB could be put down.

We also found 1 reason why the house was so drafty. At the time it was built, they used what is called balloon framing. The top wall plates were actually 12-16" above the existing ceiling. This caused the wall cavity to be exposed to the attic and the heat that leaked into the walls had a stovepipe effect, as it allowed the heat to dump into the attic. We did fill all the cavities with blown in cellulose before cutting them down to put the floor down.

We tried to do what we could with the crawlspace under the house too. There was absolutely no insulation under there. We found the floor joists to also be anywhere from 14-20" apart and this makes it difficult to go with bat fiberglass insulation. We tried to install it by using stiff wire to run from 1 joist to another and hold it in place. It worked fine on the narrower pieces, but the 20" wide pieces started bowing and much has fell down. This house would have been a prime candidate for spray in foam insulation, but with only 1 income, you have to watch what you spend.

As for reusing the existing furnace, I had plans on selling all of it in the spring as it is part of the heat pump package. The air handler part of it has the A-coil in it for the heat pump. I am going to have to rethink it now to see what I want to do. It is a downdraft furnace and it has a plenum underneath it that is approximately 24"x30"x10". There are about 4-6 different 6" galvanized round ducts that feed from there to all 10 of the different floor registers. The amount of crawlspace on the back end of the house makes it nearly impossible to run back there. Most of them were installed before the flooring was put down as they are additions to what was here.

Back around 1995 when her parents owned the house, he had vinyl siding installed. The problem was that the house had masonite lap siding on it before then. When the contractor put the siding up, they simply installed the 1/8" thick fan fold foam insulation over the masonite and then vinyl siding onto that. We started to replace a couple of windows after we moved in and found the masonite had rot on it. At that time, we removed a whole wall of siding and found it was all over. We removed the masonite, installed fiberglass bat insulation in the wall cavity and then put 7/16" OSB on and then nailed the vinyl up to it. In the next couple of years, we slowly removed the vinyl and masonite, installed insulation, OSB, house wrap, then the siding. The only wall that still has masonite on it is the 1 behind the chimney. That wall is 16' wide and we have insulated it from the inside of the house when we put up new panelling.
 
laynes69 said:
I'm not a big fan of the all in one units. Too many things can go wrong, plus you may be efficient on one side, but its never both. From the way your talking about the ducting, you would need a downflow setup. Its something that you need to be careful with. You would probably need a heat dump like you said in case of an outage, and you need to follow ducting clearances to combustibles. You would need to insulate your ductwork also running it through an unheated area. Whats wrong with the masonary chimney? Depending on its condition, you could line it and insulate and it would be just fine. You should get a rough idea on how many btus you need to heat the home with. Also when doing the ductwork, it should be sized correctly. Otherwise you will still have hot cold spots in the house. Sounds like a large project. It won't be cheap. I agree with the air sealing and insulation.

Considering the cost of the all in 1, I have been thinking about 2 different systems also. One of the main reasons I wanted the wood/propane all in 1 is because with where the current stove/chimney is, I could do anything with chimney I wanted. The current heat pump/furnace is in the center of the house which now has an upstairs addition above it. Wife does not want a stovepipe/chimney running up thru the upstairs room.

The reason I was considering removing the current brick masonary chimney is because I am not sure about it. The only way my Buckstove wants to burn properly is by running a pretty hot fire in it. We can only accomplish that now by having the door cracked for a pretty good while to get it cooking. I know the wood I am using isn't properly seasoned and is causing part of the problem. I also blame part of it on the amount of masonary here that is having to heat up before it wants to draft properly. The brick part of the fireplace area in the house is 5' wide and 4' tall. The fireplace opening is 36w x 24h x 24d. At the top of the fireplace opening, there is what appears to be a crack from the opening all the way to the sides. On the inside of the chimney, it appears to have some sort of a metal plate running the whole width of the the chimney in the flue area. From the edge of this metal plate to the inside of the exterior wall of the brick, there is about a 3" opening all the way across the fireplace opening. The outside of the chimney is all brick and is also around 5' wide at the base and tapers after it gets around the area of the top of the fireplace opening. There are actually 2 clay liners in the chimney. I believe the inner one is 7" x 7" inside and just fits inside the larger one. I think the larger 9 x 9 (?) one ends near the top of the metal plate I spoke about earlier. This plate appears to be set into the brick to help support it. Her dad built this fireplace/chimney back in the mid 70's (before we met), but I do remember him having me to put the 7x7 liner in it to increase the height as he said it wasn't drafting well enough (mid 80's). From what I recall, the 7x7 liner only went into the 9x9 by a few inches and he had me to put mortar over them where they came together. I would guess that from the bottom of the fireplace opening to the top of the 7x7 liner, it is about 16'. I have looked up in it a couple of times, but this is the best I can remember. I also went outside today and looked at the chimney. When I did, I noticed what looks like a small crack running about 2' up the middle of the 9x9 liner. I never saw any smoke so I can't verifiy whether the crack is superficial or all the way thru.

From what I remember hearing her dad say, the oil furnace he had in here when we moved in was a 100,000 btu. I know it didn't take long to heat the house up on the coldest days and the heat was hot. He started having problems with the furnace a year or 2 before he died, but it was over 25 yrs old then. When we moved in, it was in August of 2000. By the middle of September, the climate called for heat and it was hit and miss. That's when the oil furnace came out and heat pump/electric package went in. If I recall correctly, the furnace uses a 20kw heat strip. Don't know how this relates to btu, but I can tell you, after the electric heat has kicked on and ducts have had a chance to warm up, the heat coming out of the register is 110-120 °F when it is around 20°F outside. I know that just about any wood furnace can handle this temp without a problem.

I know all this can get expensive, I will be doing all the labor myself. I am somewhat of a MacGyver when it comes to projects. I will also be looking around for after season promotions on wood furnaces, as I can only afford to have my champagne on a beer budget. ;-)
 
Things are hard to accomplish sometimes when you have a place like that. It sounds just like this place. 25 years ago dad had the same problem. Oil was too much and he wanted wood but didn't have a chimney because the oil furnace was using it. He decided it would be smart to have a 90% efficient LP furnace installed. The furnace didn't require a chimney so that was taken care of. Then he went to tractor supply and bought the same furnace they still sell the 1537 and installed it beside the gas furnace. It heated this old house for years. When we bought the home from them I decided to do away with the old woodfurnace and install a EPA model.
Here this year I sealed 32 cavities in our attic that were open just like your home and it made a world of difference. As far as firebox size goes, don't let it fool you. Mine is 3.5 cu ft and I get overnight burns without any problems. Even when theres a good call for heat most of the night. Its all on how the furnace is designed. Its understandable about a budget. I would look at the englander wood furnace. Keep an eye out at your local home depot and this time of the year they may go on sale and a good deal could be had.
 
Status
Not open for further replies.