Do stove-mounted blowers inhibit combustion efficiency?

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Maybe it's a BK thing, due to the cat being right below the top which is being cooled by the fan, as mentioned by CowboyBilly, but this provides at least one example of the fan affecting the burn. Running the fan on a BK = shorter burn time.
 
Other thoughts on using fan near or on stove;
Would cooling the stove surfaces cause more creosote to condense out on stove walls before it get to flu?
This may be a plus point.

The hotter the stove the more the air will rise off of it and stick to the ceiling.
Having a window fan flowing gently in the room helps mix the air so it doesn't layer out. This makes it more pleasant people height.

A fan directed onto the stove will remore much more heat than no fan. This is probably mostly good because I think the idea is to remove heat from stove and put it into the house. Puting more heat into house and less up flu sounds good to me.

Cleaning inside of stove top?
I have never heard of cleaning the soot off of the inside of the top of the stove above the secondaries and baffle. I did this and found a great difference! Some stoves make this area inaccessible so you don't know it is getting a pretty good layer of insulating fluff and gunk. Since you regularly see flames licking up into this area I was surprised it wasn't burnt perfectly clean.

Before cleaning, stove top temp was compared to flue temp.
Notice how they track to one another, like maybe 30% apart.
Then clean the inside stove top and watch temps again. Mine was now tracking almost a 2 to 1 difference compared to about 30% before.
This experiment is best done with a medium fire.

Basicly the insulating layer of soot was not letting the heat pass through the stove top.
 
A couple of times a season I pull our burn tubes, drop the baffle and remove the ash or soot. It does make a difference. I did it with our old furnace also, doesn't take much to reduce the heat transfer.
 
Direct experience of some seems to show that having blowers reduces burn time (makes it burn quicker).

I can't think of any simple reason why that would be the case except for more airflow into the firebox. In other words, maybe it's nothing to do with the heat removal/circulation around the outside of the stove having some impact on combustion efficiency, just the extra circulation means more air going in.

I'm guessing the simple answer might be the best here.
 
cottonwoodsteve said:
Cleaning inside of stove top?
I periodically scrape off the build-up from the interior without removing the baffle and once a year, do a thorough cleaning. My stove is OAK fed cold air so those surfaces are not always hot enough to prevent build-up. Cleaning the surfaces improves the preheat on the combustion air, thereby improving combustion.
 
The response total;
Nobody has any opinion on, "does cooling the stove with a fan help or hurt creosote in flu?"

Two other people regularly clean the underside of the stove top above the burn tubes. This is interesting.

FYI;
I have a Magnolia stove. It has a stamped plate of metal with rolls that make the burn "tubes". This is welded into the top of the stove.
You can only see into the area above it with a dental mirror from the front or a larger mirror with the stove pipe removed. With pipe connected in use, there is no access to it except with a long narrow bottle brush. The only way to clean it is to blindly jam around with a brush that has to be pre bent to get into there. Then check with a mirror to see what you have done.
 
cottonwoodsteve said:
The response total;
Nobody has any opinion on, "does cooling the stove with a fan help or hurt creosote in flu?"

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I've got an opinion on everything I just dont always share it, if it is a fan that was designed for the stove-no, flue temp gauge should answer that question for you, when my fan is running it does not drop the flue temp at all just stove top temp.
 
You could get maximum burn times, super burn efficiency, and not get a bit of heat out of the stove.
If you measure efficiency in terms of heating your house (which should be the case), then the blower definitely helps.
 
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