Blower high or low on insert?

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Wolves1

Minister of Fire
Nov 15, 2014
582
Malverne ny
Temps just started getting colder in Long Island ny. Just trying to see if the blower would be better on high or low for over night burn. I have the regency ci 2600 if that makes a difference.
 
Generally, I use the blower on high when I have the fire really going hot, overnight the fire dies down in the early am so I keep it on lower setting.

I suppose the only drawback is noise if you want to keep it on high during night-time.

BTW, on Long Island here too.
 
It doesn't matter WHERE you set the blower control.
It has NOTHING to do with the actual combustion of the wood
that is INSIDE the firebox.
All the blower does is move air around the OUTSIDE of the firebox
& farther out into the room before it rises to the ceiling...
 
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It doesn't matter WHERE you set the blower control.
It has NOTHING to do with the actual combustion of the wood
that is INSIDE the firebox.
All the blower does is move air around the OUTSIDE of the firebox
& farther out into the room before it rises to the ceiling...
I wasn't sure if the blower on high would cool the metal in the chamber to fast and blow cooler air.
 
I wasn't sure if the blower on high would cool the metal in the chamber to fast and blow cooler air.
I've taken the heat measurements. It does. I operate my blower in "Auto" and as speed goes up metal temp, both of exchanger and stove, goes down.
 
It doesn't matter WHERE you set the blower control.
It has NOTHING to do with the actual combustion of the wood
that is INSIDE the firebox.
All the blower does is move air around the OUTSIDE of the firebox
& farther out into the room before it rises to the ceiling...

Yes, if you don;'t care about the noise and it doesn’t get too hot in the room just leave it on high. The air will be cooler, but warmer than the air in the room.
 
I think it does matter if the blower is on high or low. If it is on high the net rate of heat exchange from the firebox to the external environment increases. This modifies the balance between heat generation (from combustion) and heat loss (through heat transfer into the house, up the chimney, as well as the cooling effect of the combustion air supply), which is what determines the steady-state operating temperature inside the box. If the heat flow out goes up (due to higher fan speed), then you will need to run a higher combustion rate to maintain the same firebox temperature. This is achieved by more fuel (stuffing the firebox, smaller splits, etc), and/or by supplying more air. If you don't make any adjustments, then you will drift down to a lower temperature steady-state condition in the firebox. The thing you want to avoid is drifting down to such a low temperature that you can no longer support secondary combustion. Then the whole burn goes down the tubes.

I think what I wrote makes physical sense. I'm not 100% confident that it's a very big effect. My anecdotal experience suggests that it is significant enough to notice. I'd have to take some detailed measurements to know for sure. But that's the way I think about it.

-Jim
 
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determines the steady-state operating temperature inside the box.
If it's a cat insert, it'll affect the cat temp as well. I can tell the difference in the intensity of the glow when the blower is off, low or high. If I've got quite a bit of wood gassing and the cat is really cranking, the blower doesn't have as much effect. But if trying to run low and slow, you are closer to the balance point; You could even crash the cat, though that's pretty easy to avoid, and not generally an issue. Now, the OP's insert is a hybrid, so there's another variable...
 
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I'm with Jim. My lopi likes to run good and hot. If I have the blower set too high I cannot maintain secondary burn and end up going through wood faster because I have to add more primary air. I'm burning good seasoned ash. My stove likes running the fan at about half power. I'd use high only for short bursts to heat the room quickly.

Same argument with too low of a fan speed though... then I'm just burning wood and losing heat up the stack. It is finding the happy medium for your stove for keep a hot fire and getting good heat output for your space.
 
My lopi likes to run good and hot. If I have the blower set too high I cannot maintain secondary burn and end up going through wood faster because I have to add more primary air. I'm burning good seasoned ash.
What type of wood, and how fast it burns, is another factor. I'm still trying to figure out the dense woods like Hickory, which seems to gas slower. This is my first year with a lot of dry Pignut and I'm thinking I may have to split it smaller in the future to speed up the gassing a bit in my cat stoves. White Ash, for me, strikes a good balance between steady gassing and a long burn, and split size is less critical.
 
Blower speed will definitely play a roll on overall stove temp. I run my blower on the lowest setting at all times.
 
If you want the most heated air out into the room/house and circulated the best, blower on high, if you don't need as much circulation or heated air movement, then set it lower.
 
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The blower on the PE is 99% of the time on low/auto. Pretty open floor plan, so the heat circulates, it just takes time to get it moving. A ceiling fan on low and set to down on the 3rd level makes a vast improvement.

I also upgraded curtains over the windows to a thermal back (for most), and that has made a huge difference in house temps (like 5 - 10 degrees !!), depending on outside temps. Hung a curtain rod over the french doors, and sewed up some older quilts with a pocket to go on the rods, and slide them over the door when I am home, same temp change as well..

These temps are a challenge, to say the least.

I've opened the connecting door between the main house and the apartment during temps like this, the heat from the 13 rolls in & up. Helps fill the void, with no change in temps where the 13 sits.
 
Fans (blowers) most definitely have an effect on stove temp. My fan speed gets varied throughout the burn. New load, temps rising, then the fans get set higher. Temps post peak and declining. fans get progressively lowered to keep box hot and maintain clean burn. Once I'm down to 300 or so fans get manually shut to keep system hot as possible until I'm ready to reload. I may be obsessing.
 
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For the most part, I use my blower on high while I'm trying to obtain my desired room temperature, once achieved, it can be lowered to medium or low, depending on outside temps, kinda like what Hog has stated.....
But nothing beats burning a full load of dry hardwood like red oak or black locust, so there is more to it than just fan speed....
 
It's been my experience the blower on high will pull the most heat out of the stove - and put the most into the room. "Technically" more heat in the room means less up the stack - which means higher overall heating efficiency. Less heat in the stack also means a bit lower draft, though you can always adjust the inlet air to make up the difference.

So the bottom line is I always run the blower full speed to get the most heat out of the wood. If it's warm in the house, I'd cut back on the wood as opposed to cutting back on the blower and sending that extra heat out the flue.
 
Thank you all. I have found the temps in the first floor do run 5 degrees warmer with fan on high with temps in the stove not effected.
 
Thank you all. I have found the temps in the first floor do run 5 degrees warmer with fan on high with temps in the stove not effected.
Wolves1, I just want to thank you for all the time you have put into answering fire junkies questions and helping out on the CI 2600. I have done a ton of research, including reading through these monster threads over the last 4 months, and it definitely swayed my opinion from going with the FPX Large hybrid to the Regency CI 2600. I have it installed two weeks ago, but the installers tried giving me their floor model from 2014. When I saw the date I told them no way...not dealing with everything you guys had to. Anyway, you've been a big help, and cut the learning time down (I HOPE) on this unit. I will of course be back on if I am wrong.

Thank you Wolves, Begreen and others. Much appreciated!!

I know this post is 2 years old, but I'm taking a stab at writing this anyway.
 
Temps just started getting colder in Long Island ny. Just trying to see if the blower would be better on high or low for over night burn. I have the regency ci 2600 if that makes a difference.
Hi I’m here on Long Island too. I just had the ci2700 installed. How long does it take for the blower to kick on when it’s in auto mode. I’m at 730 degrees for about 25 minutes now with the bypass closed and the draft midway. Debating on just turning it on manual.
 
Hi I’m here on Long Island too. I just had the ci2700 installed. How long does it take for the blower to kick on when it’s in auto mode. I’m at 730 degrees for about 25 minutes now with the bypass closed and the draft midway. Debating on just turning it on manual.
The thermostatic snap switch is located on the bottom of the stove/insert. It takes a while for a hot coal bed to develop and the mass of the stove to heat up enough to warm that area on a cold start. If it doesn't come on soon it could be that the snap switch is not making firm contact with the stove body and needs to be tightened a bit. Or it could be the switch is defective and needs replacing.
 
Thank you all. I have found the temps in the first floor do run 5 degrees warmer with fan on high with temps in the stove not effected.
Have you compared room temps to running the fan on low speed under the same outside temp?
 
So the bottom line is I always run the blower full speed to get the most heat out of the wood. If it's warm in the house, I'd cut back on the wood as opposed to cutting back on the blower and sending that extra heat out the flue.
I only do this when it is very cold outside and I am pushing the stove for heat. Our fan speed is variable so I normally run it on medium with the weather in the high 20s to freezing and not at all if above 35º outside. Medium to low speed is reasonably quiet. Running the fan on high is too noisy for me in our living room, so I only run it on high if really needed. It's one of the reasons I sold the pellet stove.
 
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