# btu output

Posted By chrisasst, Mar 18, 2013 at 7:10 PM

1. #1

### chrisasst Minister of Fire 2. NULL

Aug 13, 2008
1,276
22
Loc:
cortland ny
How can I determine how many btu's my stove(s) are putting out?
I am asking because I am looking to install a propane furnace (55,000 input, 81% efficient) . I am trying to figure out an approx. number of gallons it would use if I ran it 24 hours like I do my pellet stoves.

I know if I ran my stoves together on max, they would put out what 50,000 btu's??
I have the PDVC set around heat #5 or 6 most times on a TSTAT, The EF2 I usually run 1/2 or 3/4..

2. #2

### jtakeman Minister of Fire 2. NULL

Dec 30, 2008
13,497
1,573
Loc:
Northwestern CT.
How many bags of pellets do you burn a day? Each bag weights 40 pounds and each pound is approximately 8K btu's.
Isn't propane pretty expensive?

3. #3

### chrisasst Minister of Fire 2. NULL

Aug 13, 2008
1,276
22
Loc:
cortland ny
2-3 bags a day...
Propane right now from one place is \$2.49/gallon

4. #4

### subsailor Minister of Fire 2. NULL

Dec 8, 2011
1,420
384
Loc:
Winthrop, Maine
How many gallons of propane will you be using a day?

5. #5

### chrisasst Minister of Fire 2. NULL

Aug 13, 2008
1,276
22
Loc:
cortland ny
Well, if I just ran a propane furnace, I would say around 9 gallons a day. ( 40,000 btu) correct?

I guess there are other factors as well right?
~~Efficiency of pellet stove vs. Propane wall furnace?
~~The location of this wall propane stove will be in the center of my room unlike the pellet stoves are at both ends.

p.s. wife says when we get the furance that we get rid of the pellet stoves. I am telling her that it will cost alot to do that.

6. #6

### stovelark Minister of Fire 2. NULL

Oct 10, 2009
1,121
200
Loc:
SE CT
Hi chris- if you use about 100 lbs of pellets a day now thats about 800000 btus x stove eff (around 80% lets say). So you use about 650,000 btus/24 hours of output heat. Thats about 25,000-30,000 an hour. Are you now heating around 1200-1600 sqft?? About that furnace, assuming its hot air?? I thought furnaces were designed ideally to have a 33-50 percent duty cycle, meaning to run 8-12 hours on a cold day. Going one step further, they are usually rated higher btu outputs too, usually 80-150000 btu depending on home size. Is this a free standing or central heating unit?? Sounds a bit small, and of course I'm using lot of assumptions. Hopefully some HVAC home design guys will jump in too. As far as run time for propane, a gallon has about 92000 btus per gallon. If your 55K btu furnace was maxed out, about a gallon every 1.67 hrs of burntime. 2.50 for propane sounds pretty low. If going with 12 hrs a day burning at max thats about 7 gallons of propane a day. Depending on what you paid for your pellets, I'll use 1.5 tons a month x 250 equals 375.00. If 7 gal of propane per day, 210 gall a month x 2.50/gal thats about 500 bones. So if you add in elec for pelletstoves and pay yourself 100 bucks for the work involved, its about even. Good luck.

7. #7

### stovelark Minister of Fire 2. NULL

Oct 10, 2009
1,121
200
Loc:
SE CT
Hi chris just saw your above post- its a wall unit- direct vent?? Those are about 80-85% efficient, and yes your est of about 9 galls a day is good. Is 2.50 a gal a heat (300 plus gallon rate)?? Here in Ct, it avgs about 3.00/3.25 for a gall heat rate. Good luck If you disconnect the pellet stoves, better keep one around for just in case sake.

8. #8

### chrisasst Minister of Fire 2. NULL

Aug 13, 2008
1,276
22
Loc:
cortland ny
Thanks for the input... yes it is a wall unit, direct vent. The specs says it is 81.5 Efficiency. This unit still uses electric for the fans or whatever...
I will double check tomorrow about the price of propane. Maybe the \$2.50 I got was a contract or something.

9. #9

### subsailor Minister of Fire 2. NULL

Dec 8, 2011
1,420
384
Loc:
Winthrop, Maine
Even at \$2.50 it's going to cost you more to heat with propane vs pellets.

10. #10

### Brewer Member 2. NULL

Dec 17, 2011
85
2
Loc:
West central ohio
Looks to me like 2-3 bags pellets a day is \$8-\$10 versus 9 gallons propane @\$2.50/gal. being \$22.50.
I bet the pellet heat is alot more comfortable....

11. #11

### stovelark Minister of Fire 2. NULL

Oct 10, 2009
1,121
200
Loc:
SE CT
Ok Chris the gas stove sounds nice nicer flame picture too, reliable source of heat if power goes out too minus the blower, if its a millivolt system. Gas (propane) is usually a little more than pellets, sometimes nat gas is the best value. One can build a case for any kind of heat, there are pros and cons. How close to house size?? who is mft of gas stove?? There are a lot of nice ones on the market, and their flame pixs are gorgeous too!

12. #12

### chrisasst Minister of Fire 2. NULL

Aug 13, 2008
1,276
22
Loc:
cortland ny
good comparison....

13. #13

### stovelark Minister of Fire 2. NULL

Oct 10, 2009
1,121
200
Loc:
SE CT
To be totally fair though, pellet cost would be about 4 to 5 dollars per bag so 12 to 15 dollars a day. 200 to 250 dollars a ton pricing. Better pellets normally around 275-300 a ton here in CT..

14. #14

### Brewer Member 2. NULL

Dec 17, 2011
85
2
Loc:
West central ohio
Ok....lets be totally fair .....say he' s paing \$7 a bag@ 3 bags/day. Still cheaper.
And i have to admit, we're pretty spoiled on pellet prices here in ohio.
I consistently pay less than \$3.50/ bag for good pellets...somersets, prestologs.
I feel for you folks out east .

15. #15

### stovelark Minister of Fire 2. NULL

Oct 10, 2009
1,121
200
Loc:
SE CT
My apologies Brewer, got locked up in my local prices- good for you if u can get pellets that low. Pellets here are still the best bet after wood and probably nat gas very good value here about 2.00/therm last I heard. Anyway no offense meant..
myself not checking the area u were in, wished we could get ur pellet prices too... Good luck

16. #16

### chrisasst Minister of Fire 2. NULL

Aug 13, 2008
1,276
22
Loc:
cortland ny
Yeah, those prices would be nice. \$4.18 / bag here. Which is not bad considering....

17. #17

### Brewer Member 2. NULL

Dec 17, 2011
85
2
Loc:
West central ohio
Stovelark,
No apology needed and no offense taken.
It's all good.
That's what makes this such a great forum, all the different perspectives coming together. (IMHO)