Finding out if furnace will heat home before winter

Finding out if furnace will heat home before winter

PostBy: jimbo On: Thu Sep 11, 2008 8:12 pm

Is there any way to tell how good furnace is going to do during the winter before winter hits?
I have fired my furnace 2 times and it seems to heat ok but it has not been cold enough (40 degrees) to know how well it will do when it is good and cold out.
The furnace 160k BTU has a fan that has 3 speeds 1800 cfm (high) 1500 cfm (medium) and 1150 cfm (slow). I have not got a cold air return hooked up am just using basement air as it gets warm down there with the coal furnace being down there. I do have hot air tied into the hot air plenum of the oil furnace with back draft preventer (12 inch round line) and am using the ducts from there. The coal furnace seems to move nice steady heat but does not have a lot of force won't move curtains but will blow a pc of paper off register. The fan on oil furnace does not come on hot air plenum on oil gets up to 110. Coal air fan is set to come on at 150 and off at 100. I have added a second temp probe for control of oil plenum fan so I have independent temp control.
When it has been 40 degrees out I leave my screw out draft at 2 turns and house stays 72 to 75 degrees.
Oil furnace is 100K BTU I hope this makes sense I dont want to get caught in the middle of winter and have furnace not able to do the job.
jimbo
 
Hand Fed Coal Furnace: Fire Chief 700
Coal Size/Type: Stove or nut
Stove/Furnace Make: fire chief
Stove/Furnace Model: fc700

Re: Finding out if furnace will heat home before winter

PostBy: BIG BEAM On: Thu Sep 11, 2008 11:33 pm

That one 12" duct connected to you oil furnace is not all that big for a 160k furnace.BUT I think you'll find that with coal the fan will run continously.This is not a bad thing(mine does) and will keep the house more even.The oil furnace comes on and off.Makes a lot of heat then turns off.The house gets warm then cold.You can play with the different speeds on the fan and the fan switch so that it will run continously that is what you're shooting for.You might have to disconect one of the return ducts from the oil furnace and leave the grate open to the cellar so as to get enough return air to the coal furnace fan.

I have my furnace feeds hooked together like yours and hooked up 1-10" return to my coal furnace.Works great.but remember you can always play with it latter in the season.
DON

If worst comes to worst you can always add another feed duct to your oil furnace.
BIG BEAM
 
Stove/Furnace Make: USS Hot blast
Stove/Furnace Model: 1557M

Re: Finding out if furnace will heat home before winter

PostBy: coaledsweat On: Fri Sep 12, 2008 7:57 am

With 100 BTU/oil and 160 BTU coal, you have about twice the BTUs you need with the coal appliance. If you have enough hot air duct and a cold return, you will be sweating bullets. :)
coaledsweat
 
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

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Re: Finding out if furnace will heat home before winter

PostBy: LsFarm On: Fri Sep 12, 2008 7:08 pm

The key to getting more heat out of your furnace will be designing and installing a cold air return duct system.. If you currently can't easily overheat the house with your furnace, I'd plan on hooking up a cold air return later in the season. You will be reheating warm air, instead of cold air from the basement, this will make keeping the upstairs warmer much easier.

Even if you do have to burn your regular heat system ocassionally in really cold weather, you will have put a significant dent in your heating bills with your coal burner.

Greg L
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Re: Finding out if furnace will heat home before winter

PostBy: jimbo On: Sat Sep 13, 2008 7:22 am

My basement is not cold it is warmer down there than the 1st floor.
I am not heating cold air that way it is actually drawing the warmer air from the basement.
The furnace does have a filter box installed so it is filtered air.
I may have to just wait and deal with it as the temps outside get cooler.
I have thought about insulating the 12 inch hot air pipe that goes from the coal to oil furnace this would help I am sure as well as tape the seams with high temp tape.
I have noticed a few air leaks around the jacket of the coal furnace when blower comes on where jacket wraps around the front of furnace.
I will seal these with high temp silicone.
I have a local guy that is a furnace guy and will get him to come over and take a peek at it.
jimbo
 
Hand Fed Coal Furnace: Fire Chief 700
Coal Size/Type: Stove or nut
Stove/Furnace Make: fire chief
Stove/Furnace Model: fc700

Re: Finding out if furnace will heat home before winter

PostBy: LsFarm On: Sat Sep 13, 2008 10:42 am

Hi jimbo, think of your upstairs as a balloon or a sealed box.. you are trying to inflate the box with hot air,, a sealed box can only take so much air untill it reaches a max pressure point. excess air must be allowed out of the box before new air can get into the box.

You have to think like a HVAC [heating /ventilation/air conditioning] installer.. You cannot force hot air into the upstairs with out removing some of the cool air from the same part of the house.. You must create a circulation loop.. ALL properly installed furnaces have a cold air return ductwork. or they don't work very well.

Right now, you may have a warm basement, but where is that heat coming from??? Is it radiant heat from the furnace?? or is there a doorway from the upstairs open letting air from upstairs into the basement?? Either way you will have a much more efficient furnace with a cold air return hooked to the fan/filter intake of the coal furnace..


Greg L.
LsFarm
 
Stoker Coal Boiler: Axeman Anderson 260
Hand Fed Coal Boiler: Self-built 'Big Bertha' SS Boiler
Baseburners & Antiques: Keystone 11, Art Garland

Re: Finding out if furnace will heat home before winter

PostBy: BIG BEAM On: Sun Sep 14, 2008 7:29 am

One of the things I did because I have an old house with old windows was to use a little air from the cellar 5 or 10 % as return air.This will slightly presurize the house so instead of cold drafts coming in the house a little warm air leaks out of the house.It may be all in my head but the windows seem less drafty.
DON
BIG BEAM
 
Stove/Furnace Make: USS Hot blast
Stove/Furnace Model: 1557M

Re: Finding out if furnace will heat home before winter

PostBy: coaledsweat On: Sun Sep 14, 2008 2:33 pm

It is less drafty.
coaledsweat
 
Stoker Coal Boiler: Axeman Anderson 260M
Coal Size/Type: Pea

Re: Finding out if furnace will heat home before winter

PostBy: BIG BEAM On: Sun Sep 14, 2008 8:28 pm

What made me think of that was when ever you walk in a big store or mall in the winter the air in the building hits you in the face when you open the doors.I had a chance to talk to a HVAC guy once and asked him why.That's when he told me that they run a slight positive presure in the buildings.Then he said did you ever walk in a store and your ears pop.That's because the presure is to high.

Like my gramps used to say if you don't know....ask someone.
DON
BIG BEAM
 
Stove/Furnace Make: USS Hot blast
Stove/Furnace Model: 1557M

Re: Finding out if furnace will heat home before winter

PostBy: jimbo On: Fri Sep 19, 2008 5:50 am

It has been cold here in the evening so I started the furnace on Tuesday evening temps were in the 40's or low 50's at night and warm up nice during the day.
This morning it is 29 degrees out and I have still got the same fire that was started on Tuesday going. I have added a few shovles of coal to fire but feel good about being able to keep same fire going.
The temp inside this morning was 76 degrees when I got up and the furnace is not working hard at all to do it. I have the screw type draft in the ash pan door and have had it set at 1 turn out. I have checked the draft with manomter a few times and played with the baro and I think I am running about .07 for draft.
I am not going to change anyting for now going to wait for some colder nights and see how it does.
I did seal the air jacket with high temp silicone where had a few leaks have not insulated the duct yet. The stack temp was 125 before I opened up damper this morning to shake it down.
May seem like a waste of coal but I do not want to here the rumble of the oil sucking beast I would rather waste cheap fuel that burn any of that LIQUID GOLD.
jimbo
 
Hand Fed Coal Furnace: Fire Chief 700
Coal Size/Type: Stove or nut
Stove/Furnace Make: fire chief
Stove/Furnace Model: fc700

Visit Hitzer Stoves