Add on furnace question

Not sure if I'm in the right place or not but I'll try anyways. I'm a new member from the upper peninsula of Michigan, I bought my first house this past summer and it has a Vogelzang vg 2500 add on furnace in the basement. I have a propane boiler with hot water heat backup on the other side of the basement with baseboard throughout the house. The wood furnace has 2 8" pipes coming from the top about 3 feet high with 45 degree Elbows acting as directional blowers simply blowing hot air from the furnace. The wood stove works alright with moderate temperatures but last weekend it got to -25 f and my house was cold. I'm also using a lot of wood being that I'm counting on heat simply rising through the floors. I knew going in I would have to make changes but I'm not sure what the best route is. My question is can I put a floor vent in the floor above the stove and run duct work directly from the furnace blower through the vent? I'm not thinking directly above, but it would be in the area above the furnace. I was thinking I could put another floor vent in the opposite end of the house to work as cold air return. My house is about 1700 square feet 1.5 story open concept design. Thanks in advance for the help

 

Do you have an insulated Plenum which is a big box that sits on top of the furnace to store a large quantity of hot air before the blower kicks on. The blower then kicks on when the temp in the plenum reaches a designated level and then the blower kicks off when the air temp in the plenum drops to a designated level.

The ideal situation is to have a insulated plenum sitting on top of the furnace then a main duct running from one end of your basement to the other end. This main duct is hooked to that larger plenum, the plenum feeds that main duct. Then put you in some vents upstairs at the outer ends of your rooms as the center of the house and the center of the rooms are easier to heat so you place the location of your vents on outside walls of the rooms and under windows that are drafty to get heat to those locations better. You can use flexible round duct work coming off the main duct to go to these vents. You are large of main ductwork as you can and use as large of round flexible duct as yo can as volume of air is important as you want the largest amount of air flow as possible.

Dont forget a return duct from upstairs also and it should have a filter install inline with it to keep your air clean from the dust and dirt of the wood furnace. The return duct feeds into the suction side of the blower housing. You should have that filter right there at the blower housing.

Getting the plenum furnace fan limit switch set for kick on and kick off setting is something to play around with to get it just right. On the fan limit switch there is a manual pull fan switch to have just the blower run all the time if you want. On my set I had years ago my blower was 3 speed so I would set it to the lowest blower setting and pull the manual switch to let the blower blow continuously on a low blower setting, especially when it was minus temps outside.

Looks like this:

 

Thanks for the reply,No plenum and no duct work at all. that's kind of my problem....looking for a better way to get heat up stairs without breaking the bank. The house actually heats pretty evenly now, just looking for more efficient way to heat because this has been a mild winter and I don't see the stove keeping up with a normal UP winter.

 

Welcome to FHC
I wish I had some valuable advice to offer, but just giving a shoutout to a fellow yooper

 

Hi Matt, welcome to FHC.
Is this your unit?
The first thing I'd do is read through the install manual...available on their website if you don't have it.
This furnace is designed to be used as is, no additional plenum needed (the jacket of the furnace is the plenum in this case) You can run (2) 8" metal (no flex duct allowed on solid fuel furnaces, it's against NFPA code) to wherever you choose (not too long of a run though, the air will cool too much) terminating into a standard furnace supply register, either in the floor or the wall. Obviously in the floor makes the install a bit easier, but in the wall is not that hard either.
As far as return air, you hafta have it, so you can either allow the air to return down a stairway, or a dedicated vent. If you use a stairway, it must be made so that it cannot be closed off when the furnace is running. Either remove the door or cut vents into it. Or you can install a dedicated return vent also, but if it is not ducted back to the furnace, it will have to be a fire rated register (it closes in event of a fire) If it is ducted back to the furnace it will be slightly more efficient than the other way.
Oh, and the supply pipes have to be kept 6" away (at least) from any combustibles for the first 6' of horizontal run. This actually works out pretty well on a wood furnace because you need to keep good rise on your run so that you will get gravity heat flow in the event of power failure.

 

Thanks for the replies, and a special hello to fellow yoopers! Brenndatomu thanks so much for the help! That is the furnace I have and I will be doing that this spring. That makes me feel better that I can safely do that because I've been racking my brain around ideas this winter, even contemplated going to a OWB down the road. Thanks again for all replies looking forward to learning more from this site.

 

Matt, one option to consider providing funding and adequate space is available within the unfinished area of your basement would be to have a complete supply and return air duct system designed and installed. It may be a bit tricky working the supply air ducting and return air panning to and from the wood furnace around your boiler piping, but it should be doable. Of course if the basement is a finished space, this is a moot point.

The two 8" rounds could supply adequate airflow into a supply air trunk, that of course would be tapped with the appropriate 6" round 'take offs' to supply a network of floor registers. Its not unheard of to adjust the opening(s) on top of the furnace to a much larger square or rectangle to allow yet a larger plenum to collect heat off the heat exchanger, then transition that to an appropriate size duct to carry it to the main trunk mentioned above. There are static pressures and air velocity charts and graphs that show duct sizing requirements for a predetermined air flow but thats another topic for later and probably a moot point also at this stage of your game.

If adjustments to the wood appliance top is seriously considered, a call to the manufacturer should be made to ensure there is no warranty violation. There is USUALLY no issue as the two 8" rounds create much more airflow restriction at the top of the heat exchanger than a 16x16 (or other maximized opening) square. You would find that the design of an adequate return air network to be possibly the greatest challenge of your particular installation.

Yep, way over the top as far as expense is concerned, but at least it is a viable option (and just ONE of a number available), providing the previously mentioned criteria is met.

Good luck sir, and please keep posting updates with the route(s) you've decided upon....Oh, and a hearty welcome aboard. I'm a Newbie to the Forum too !! If we are lucky, they (Powers That Be) won't kick either of us out !!

 

If your on a budget just running a few sections of 8" duct along the ceiling (maintaining clearances) and terminating it at stairwell will help get heat up stairs. As it is your just heating the floors of your house and the basement.

 

Another way to approach this is to insulate the walls of the basement (assuming its not already done). In doing so, you'd minimize your heat loss from the basement and increase the radiant heat that you receive through your floor.. This of course wouldn't work so well if you had insulation on between the joists of your first floor or carpeting on your first floor. If you like a cold basement, you wouldn't have that anymore but from an efficiency perspective, an insulation project would definitely help over the long term especially if it negated the need to install ducting... There are several folks on this forum who are "cellar dwellers" and heat with an appliance in their basements..

Here are a couple of links. Assuming you are burning dry wood?

Basement Dwellers club Poll: | Page 9 | Firewood Hoarders Club

basement stove | Firewood Hoarders Club

 

Here is a back view of that furnace.

You need to build a metal box around the motors and have a place to slide in a furnace filter.
Then hopefully you can bring down a return air duct to hookup to where the filter is and seal
off the whole return air path so no leaks. This way the already warmed air you have blown up stairs is recirculating thru the stove and warm air is easier to heat than cold air. Its like the recirculate in your car or truck heater.

Then run a couple ducts to registers thru the floor and make sure those ducts are "not" right above the stove as it is easier for fire to spread if you place the duct right above the stove. But your insurance Co.might not like that. I would place the ducts at outter ends of the house as the outter ends are the hardest to heat rather than letting all the heat come up in the center of the house.

You can buy metal foil tape to seal all joints.

 

Here is the manual

 

Welcome aboard Matt.

Where are you located?

What type of heating system does your house have now?? Hydronic? (boiler) Or just the wood furnace?

There is absolutely no ductwork existing? How old is your house?
lots of questions, I know.

PM me if you wish. Some important things I can share.

 

Thanks again, I'm going to run some duct work this spring with a return. I already have a box with filter around my blowers so I might tie into that. Luckily El Niño is keeping the temps above normal so the house is warm and around 70 to 72 degrees. I will put a fan at the top of the stairs should we get another blast or really cold weather. If not I'll make it through this winter and be much better prepared for next winter! You guys have been a big help and I'm learning lots reading around this site!