Will a Blower Shorten Burn Times?

Hi there. Last year I burned Pea coal from Blaschak in my Mark 1. This year I went to Nut because I heard that burns better in this stove. Well in addition, I have been running my blower 24/7 and I am not getting the burn times I expected. After 8 hours the load is mostly burned up and I am haveing a bitch of a time getting it going again. Ideas?

What Rob R said Personally, I never use my stove blower. I have a ceiling fan that distributes the heat that really meets my needs. This old farm house is so broken up--the blower was just dealing w/ the room it is in--the ceiling fan get the heat all over the house

Do you have a reastat on the fan or is it full tilt all the time? The fan should have no bearing on burn times but it will cool the stove a bit as it scrubs off the heat into your house and if now with the fan you are giving the stove more air then you were before to maintain your stove temp this could explain your shorter burn time. Fan may be pushing to hard.

Bootstrap wrote:Hi there. Last year I burned Pea coal from Blaschak in my Mark 1. This year I went to Nut because I heard that burns better in this stove. Well in addition, I have been running my blower 24/7 and I am not getting the burn times I expected. After 8 hours the load is mostly burned up and I am haveing a bitch of a time getting it going again. Ideas?

I'd say you were not taking into account that the pea is more dense
and you have actually more "fuel" in the stove, at the same given height.
So if you fill to say, the top of your brick, you have less coal
in the stove than with the pea...

That and as mentioned the pea burns slower, AND cooler
usually, with the same air intake openings.
Sometime people talk about longer burn times with pea.
Yes, but it's because of lower stove temp and more fuel in the stove..
You should get pretty much the same total "heat" no matter which you use.

The coal bed doesn't know if there is a blower going or not.
The blower is a different function of your stove.

Dan

Chuck, What kind of burn times do you get with your mark 3?

I get at least 24 hour burn times with my TLC 2000 but I added extra horizontal brick on the top so I can load it up higher. I can usually go a day and a half when its above 40º. Even when it gets down around 30º I can go 24 hours. I don't run my stove much over 300º unless it gets down into the teens and twenties. In warm weather I like to keep it around 200º or less. I usually don't run my fan until its in the thirties and then only on low speed.
I think this is because my home is well insulated.
I'm burning all nut this year but pea burns just as good.

Bootstrap wrote:Chuck, What kind of burn times do you get with your mark 3?

That's a very difficult question to answer, at least from my point of view.
To me, I don't really look at how long it lasts, or doesn't last.
I look at how comfortable I am.

I can get a really long burn, if it's 48° outside.
But not so long as when it is 3° out.
I'm not trying to be a wiseguy!
But... there are only so many BTU's in a stove full of coal.
So if your stove temp is ~300°, you may get , for example, 18+ hours.
If your stove is ~600°, like mine when it's windy and cold, 10-12 is pretty easy.
BUT... having a fire last 12-18 hours is not always great, IF you have
to very gently add coal to it, to get it cranking happy again!
Because all that time the stove drops to 275°... you are getting cold again!

So really... what works good for me, is not going for marathon burns,
but maintaining a nice happy good sized bed of coals.
When I'm asking the stove to perform, I feed it more often,
in smaller quantities. That way, the stove temp doesn't drop
as much... the fire catches quickly, and the stove has a big happy face on.
Me too.

Monitor your stovetemp/stack temp if you don't have a manometer.
Rutland gauges, while not great, at least give you a guide line
for around $9.99 at HD, or Lowes.
Just make sure your stack doesn't get really hot. If it gets too hot,
you may have too much draft. A mano will help a lot,
not in fixing anything, but it takes away the biggest unknown:
how strong (or weak) your draft is...
Hope this helps a little..

There are a lot of seasoned folk here, all more than willing to help.

Dan

Bootstrap wrote:Hi there. Last year I burned Pea coal from Blaschak in my Mark 1. This year I went to Nut because I heard that burns better in this stove. Well in addition, I have been running my blower 24/7 and I am not getting the burn times I expected. After 8 hours the load is mostly burned up and I am haveing a bitch of a time getting it going again. Ideas?

You may have to strong a draft. I know Harman doesn't recommend it but you may want to try using a MPD or try a barometric damper. I use a MPD on cold days and leave it open on warm days. Also fill it up as much as possible. Fill it up from the top of the bricks in the front to the top of the bricks in the rear. That should give you a nice angle of coal from front to back. You can also try to pile a little more in the center.
It seems like your burning through it to fast. Of course thats ok if you want more heat you will use more fuel. Just like a car if you want to go faster.

Thats my $.02 worth.

I had the knob on the front turned up to 2 turns. Didnt burn 10 hours. Turned it down to 1.5 turns, still went out within 10 hours. Now I run it at 1 turn out, and she was still running good after 8 hours, looked like I couldve gotten at least 4 more hours out of it.

Yup...Always fill it up and use the primary air knob for how hot you want to run it. When it gets really cold I run it hotter so I use use more coal and shake and fill twice a day.
I don't have a Harman Mark series but, I seem to remember most members that do average about one turn open on the primary knob. Of course that all depends on how hot you want the stove and what you draft is like.
I don't know what the maximum temperature would be for a Mark1, but I would not go over 500º for starters.
Maybe some member with a Mark series could let you know how high they go on theirs when they really need the heat.

As others have said, the blower would make no difference on YOUR stove. A stove with a bi-matalic flapper (auto air control) will use more fuel with fan on, than fan off, at the same settings. Reason being; the fan takes heat off the stove, cooling the mass of stove body. The auto air opens, trying to maintain temperature. When outside temps are warm enough, turning the fan off helps to not overheat the house. Also has longer burn times.

Bootstrap wrote:I had the knob on the front turned up to 2 turns. Didnt burn 10 hours. Turned it down to 1.5 turns, still went out within 10 hours. Now I run it at 1 turn out, and she was still running good after 8 hours, looked like I couldve gotten at least 4 more hours out of it.

WOW! Two turns?!?!

That's a LOT of air on the Harmon.

I had a Mark I for 10 years and last year upgraded to the Mk II and unless I was really trying to make serious heat, 1.5 turns was about the max.

And my current chimney is terrible so I have to give it more air than my old house.

One thing I've learned is that I "over tend" the stove. The less you play with the fire, the longer it seems to last. I wouldn't even suggest looking at the stove for at least 8 hours after you fill it. I typically go 12-14 hours and my best time with the Mk I was around 22 hours without doing anything to it.

I agree that if you have no damper on it now, even though that's what Harman recommends, I'd at least go with a barometric if you can. In my old house, the chimney had a ton of draft and no room for a baro so I had to put a manual damper on it or I'd be going through coal like not tomorrow.

I've got nut in the stove now but depending on what the weather looks like, I may switch to stove coal around Christmas. Only if it gets cold as predicted.

To answer the question, your fan shouldn't affect your burn times, mine runs 24/7. And the stove is capable of long burn times so you just need to figure out what your particular combination wants to get you there.

Yeah, even in my house 2 turns on a Mark I was off the charts! 2 turns on the Mark III though is where it likes to be, depending on how smashed the nut coal is when I open the bag.

Running the blower will actually REDUCE draft - because your taking heat out of the chimney & putting it in your room, basically. That blower knocks about 100° of stack temp off my III.

oliver power wrote:As others have said, the blower would make no difference on YOUR stove. A stove with a bi-matalic flapper (auto air control) will use more fuel with fan on, than fan off, at the same settings. Reason being; the fan takes heat off the stove, cooling the mass of stove body. The auto air opens, trying to maintain temperature. When outside temps are warm enough, turning the fan off helps to not overheat the house. Also has longer burn times.

Yes, the combination of bi-metal air control and fan is ideal because you can adjust one or the other or both to give you a comfortable room temperature.