inserts and fan speed

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soxfan13

Member
Hearth Supporter
Nov 10, 2007
88
eastern MA
People with an insert, how do you run your fan? I feel that I get the most heat into the room by running the fan on high (makes sense right?). However, I also think that running the fan on high affects the burn time I get. When I run the fan at a lower speed I feel that I am almost wasting the heat that could be pouring into the room. I do think I am getting a longer burn time, though. Any ideas? Is running your fan on low "wasting" heat? Which way is more efficient?
 
You're right: blowing your fan in "high", extracts the most heat from the chimney. And, if you run your stove a a low temperature, you can get a higher percentage of that heat delivered to your living room with a blower. BUT.....a low temperature in the chimney increases the amount of creosote deposited on the chimney.

If you want the largest % heat in the house for the energy expended, run your stove at a low temperature, and a high blower speed. BUT, then you'll have the most possible creosote deposited. I wouldn't recommend it.


I realize I will accept "inefficency" the sake of low creosote. I run my stove hot (450-600 degrees on the insert-top thermometer) , keep the blower moderate, can still keep a conversation in the room and I don't upset my cats with a loud blower that reminds them of the *dreaded* vacuum cleaner. And twice a week I put a bunch of newspaper in the fire to have a limited high-intensity burn, hoping to burn off whatever chimney creosote I've deposited.
 
Hey soxfan, we run our 550 on high when the temps are dipping below 30. Anything north of 30 and we lower the blower setting accordingly. We have a 3000 sq/ft new colonial (well insulated) and are able to keep the entire house at 70+ degrees with the blower on high with the jotul hovering around 500. We run the blower in automatic at night and it typically shuts off before I can reload the stove at 6:30, then I get a rip roaring fire going, put in in manual (as to not waste that heat), take the kids to school, come home and throw it back in auto. I have seen threads where people thought they burnt more wood on high, however; I can honestly say that I have not seen that. I burn more wood when I am trying to run a hot fire on a cold night and it does not seem to matter where i put the blower. I like high unless I am on the phone or doing something where I need it to be a little quieter.
 
I only have one speed *FAST*. I agree running the insert with the fan off or slow speed seems to waste heat, but I would think running with the fan on should give a longer burn time. The reasoning is this: Fan on = slightly cooler stove = slightly cooler flue = slightly lower draft = longer burn. Fan off = hotter stove, hotter flue, more draft, shorter burn.

Additionally, on any modern stove, the firebox should be insulated from the actual metal of the stove, so secondary combustion is occurring in a separate space which can't be directly cooled by the fan. You should be OK to run the fan as fast as you wish - so long as the draft doesn't fall below the level which starts to negatively effect your burn rate.
 
Run the fan according to how much heat you need, and how much noise you are willing to put up with. The faster the fan runs, the more heat it pulls from the stove (obviously), and it may have the effect of reducing your draft and slowing the fire, as cozy heat said, but that depends upon just how much air the fan is capable of pushing through. When the fire is in full swing with the secondary burning clean, you can run the fan as fast as it will go and it will probably have little or no effect on the fire. Overnight, you may need to use a slightly lower setting to avoid cooling the stove to the point where you stifle the fire when it transitions to blue flame with coals. This can lead to a big pile of dead coals in the morning, unless you are in "auto" and the fan shuts off as it cools. It all depends upon your stove, and your set up, so you'll have to experiment.

Dan
 
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