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[R W Ohio]

I took advantage of this mild weather to try things with the OWB.I unhooked the blower fan motor to the stove and ran it on natural draft.The results were not what I thought they would be. The recovery time was very slow,it took over an hour to go from 160F to 180F.This wasn't a problem on this warmer day,because the load on the system was low.Another problem was that the smoke out the stack was much more than when the fan is being used.I do have 6ft. of all fuel chimney added to the stove,so it should not of had a draft issue. I think the major reason for the poor operation was,that the amount of air to the fire was not enough. I have never seen a stove that uses natural draft,but I bet the area for air to enter the fire box is larger than the opening of the forced fan.Anyway I wanted to try it to see if on warmer days that I could shut off the fan and save some electric.It did not cost anything to try,but I do not think I will do it again. Just thought I would share what I did.

[Scott7m]

i'm not a fan of forced air myself, but you can't take a stove/firebox that isn't designed for natural draft and expect it to do well that way......    like you said, the air intake on a natural draft is likely much larger... 

[jon d]

Your probably right. The size of your air inlet for your blower might not provide enough air while not running. I run a cb5036 which uses natural draft. I'm very happy with it's recovery time.  I have a question?  Do you think a forced air draft would use more wood than a natural draft. I know that both are loosing heat through the chimney. Just wondering..

[R W Ohio]

I think it's about a wash.With the longer burn times with natural draft and perhaps less heat going out than with a forced air system at the same burn time,but with the forced air systems shorter burn time and perhaps more heat going out for a shorter time it should be about even.Just my opinion.

[jon d]

I'd agree-- I have some pretty Long burn times.

[CL-Ohio]

hey R W does your OWB fan have an adjustable speed control knob, my Crown Royal does and it made a load of difference on my burn time getting the speed adjusted.

[Jason]

The air inlet on my Hardy is only about 2" square.  I know I could never run it on natural draft.  Besides, on days when it's close to or over 30* all day, the fire box is still half full when I go to fill it 12 hours later.  I'm not at all familliar with nat. draft systems, but I have no complaints about what I have.   

[MarkP]

My OWB is homemade, with a 2" square tube delivering air into the firebox, and the draft fan is 140 CFM,,,,,,,, wayyyyy too much fan.  I had considered a smaller fan, or a rheostat to control the speed of the current fan, but instead used duct tape to cover part of the air inlet.  (quick and easy)   Maybe not the best way to reduce the air, but it cut my wood usage DRASTICALLY, and the stove is able to keep up this way, and I don't have that 3 foot flame out the top anymore.    My biggest concern is how it will wear on the fan.  I'm sure it's pulling more amps to run now.  If I don't put a smaller fan on for next season, then maybe a rheostat to reduce the speed would be a better choice??

[R W Ohio]

CL Ohio

When I posted what I had done,taking the blower fan off line,it was not because I was unhappy about either the burn time or the wood usage.I am pleased with the amount of wood that I have used (or not used) this heating season,so far. What I was trying to do,was to use less electric by not running the fan motor on the warmer days.I am sorry if I did not make that clear.

Ron 

[willieG]

mark i read some place you should choke the feed to the stove  not the suction of the fan
why..i dont  remember i will see if i can find it again

[MarkP]

THANKS,,,,,  Let me know if you find it.  My biggest fear is doing damage to my fan.  I have a rheostat to install on it, but I'm not sure if that will cause damage.  The fan is a simple 2 wire fan.  I'm not knowlegeable enough on the electric motors to know if it will work OK.   Just not sure what is best.