Blow hard or soft?

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parsimonious

New Member
Dec 8, 2011
12
Upstate NY
Been tinkering with my insert in an endevour delay turning on the furnace.

Is it better to use a high setting with a high volume of warm air,or a low fan setting with less but hotter air?
I've been going back and forth between the two and trying the middle path also but can't decide.

I bought this stove in the summer to use as a supplemental heat source but now realize that I should have gone bigger.How many times have you heard that?
 
I just posted about this. My blower pulls to much heat off my insert on high. I just lowered my temp about 100 degrees in less than 5 minutes with my blower on high. That was 700 to 600 degrees. I use my blower speed to regulate my insert temps. Once my temps settle in at 550 to 500, I turn it on low/medium(my blower is variable speed). If mine was 2 speed, I would be on low at those temps.
 
Unless it's really cold out (under 15F or so), My fan is on low. The floor fan, and one ceiling fan get the warm air flowing quickly.
 
Good post, I've been wondering the same thing over the past three years.

My experience has been that for a brief time during the burn cycle, i can put the blower on high and make some serious heat. However, at the beginning and end of the cycles the blower on high pulls off too much heat. I have found a sweet spot which allows me to keep the blower on the same speed throughout the entire cycle. Giving you a speed might not help, as all blowers have different highs and lows, but i run about 1/2-3/4 speed on 180 cfm dual blowers. They seem too powerful for the stove. Another thing i will add is the fact that i try to heat more house than the stove is designed for, which makes me run the stove a little harder than i should. If i am going to be away from the house for an extended period during the day, i will put the blowers on a lower speed so i dont cool the stove too much when its down to coals.
 
yeah, I've always wondered about this as well. Blowers do cool the stovetop some, and my blower cools my T5 quite a bit on high. So I also struggle where to set my blower, and often times just leave on med low to low.

My question about that is: is that even a concern? I mean, the blower is cooling the stove top, but that heat that is being "stolen" from it, is really just being distributed in the room/house, right? So why would we care about the blower cooling the stove top (from a hot fire, of course)?
 
if it is heating your house and still burning clean, then there is no problem. If it is cooling your stove to the point of colder flue temps, then that becomes the issue.
 
I'm with others here. If my stove (insert) starts to run hot I can crank the fan up and help cool it down. The faster you move air the more it cools. With the blower you are only trying to move the warm air off the stove, not blow it out into the whole house. I find that if my blower is set about 1/2 speed (right at the point I can no longer really hear it) it works best. Once the air is off the stove the ceiling fan takes over and pulls it into the room.
 
EJL923 said:
if it is heating your house and still burning clean, then there is no problem. If it is cooling your stove to the point of colder flue temps, then that becomes the issue.


Gotcha. I guess I didn't make that connection. I assumed that the blower wouldn't have any effect on the flue temps, as the stove inside, is still burning hot (if say, with my blower on med high to high, my stove top temp is 350 -- turning the blower off, it would jump back to 500 -- safe temp).

I don't normally run my blower anywhere near high speed, unless I want to cool a stove temp that jumped to 7-750, but I've always had this question.
 
raiderfan said:
EJL923 said:
if it is heating your house and still burning clean, then there is no problem. If it is cooling your stove to the point of colder flue temps, then that becomes the issue.


Gotcha. I guess I didn't make that connection. I assumed that the blower wouldn't have any effect on the flue temps, as the stove inside, is still burning hot (if say, with my blower on med high to high, my stove top temp is 350 -- blower turned off it would jump back to 500).

I don't normally run my blower anywhere near high speed, unless I want to cool a stove temp that jumped to 7-750, but I've always had this question.



Along those lines, would I get a longer and hotter burn with my blower dialed down instead of jacked up??
 
I've generally run my insert blower on high except when we're in the room, but this thread has me thinking about coal build up. I seem to get a lot of coals at the end of a burn so I'm going to try running the blower on low to see if the higher stove temp reduces the coals.
 
Well , I decided to run the fan lower and also stop putting so much wood in the stove. The furnace is on and my money is going up the chimney and over to the middle east somewhere.
When I bought the stove my intention was to use less oil and have at least one really warm room.Somehere in the fall I forgot all about my plan becuase that little stove was doing so well.
I kept running it hotter and packing it fuller as we got closer to winter. Trying plan B when I only had the tools for plan A.

Thanks for all the replies.I'm going to sit back and relax by the hearth without trying to run the hell out of it.These Lopi's get hot when you pack them higher than the firebricks.
 
There are blowers, and then there are BLOWERS. One blower on low could conceivably move more heat than another on high, so YMMV. Likewise with various brands of stoves.

With my stove and the 650 CFM blower I use, I can certainly cool off the stove enough to take it out of the sweet spot. About 85% of the time I run the blower on low and the remaining 15% is divided between the blower being on high, off, or somewhere in between.
 
this winter i plan on installing a ceiling fan in the room where the stove is. My hope is to be able to run the stove blower lower.
 
I'm a recent stove insert convert myself and learning the same lessons. With my Jotul 450 Kennebec, I'm noticing that the blower can quickly cool the firebox. Then I find myself asking whether it is better to run the stove without the blower for substantial periods of time, or increase the air intake? I guess it's all a fair trade-off as long as the goal of keeping firebox/flu tempratures in a good range is met.

Best,
-Greg
 
to get the most BTU out its easy, move the most air!

Assuming that the blowers wont effect what is happening on the inside (they do, but probably not too much, at least on an insert). Then the heat transfer occurs quickest when you have the largest difference between the two items. So in this case, move the most air so that it doesnt heat up as much. moving half the air doesnt mean you are getting half the energy out, as its hotter, but if you move half the air, it wont be twice as hot. (half in volume, not half on the switch either).

In reality, I have an insert, without the blowers I get nearly zero heat out. I run the blower on high full time (its a switch, no speed options). free standing stove owners may disagree. Moving more air will likely heat up a bigger space in your house though, so more losses there, but it will be a bit more uniform. Less volume will mean hotter air that is more prone to go straight to the ceiling. Some people find the movement of the air might me less comfortable, so it may feel different too. higher fan speeds are going to extract more heat, but it might not be a clear winner depending on lots of variables.

Once the fire is going well, if I turn on the blower, I cant say that i see a difference in the firebox. The temperature reading of the stove will drop! But that is because you are cooling the metal from the surface in. So if your surface thermometer says 700F with the blowers off, the inside of the box isnot the same as if it says 700F with the blowers on... but you dont care since its the steel you are worried about. Since the blowers on high will pull out, say 20% more btu (just a guess), that btu is coming from the inside of the box. How that effects the burn will depend on many things (stove design, wood type, etc).

At the end. The arm load of wood you toss into the stove has a certain number of BTU, the stove can only be so efficient (usually low 70%, mine I think is 72%). after that its a question of how efficient you are operating it, and if you are trying to get all the BTU now, or have a slower fire and drag it out.
 
have you guys tried measuring a different spot on the stove? to see if the ENTIRE stove is actually dropping? or just the part where the cold air is blowing over it?
 
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