When cleaning the slider air control on my Lopi Freedom, I decided to learn what I could about how the air control works, and to see if I could find a way to override the minimum air control.
Firstly, the air control consists of two sliding plates, each with a rectangular hole, pushed up with springs against matching inlet holes on the underside of the stove. What I noticed first was that contrary to my original thought, the relative proportion of each air supply does not change with slider position. There is a triangular hole on the primary air inlet, but the matching hole on the slider is rectangular and smaller than the triangle, so the resulting opening will always be a rectangle.
My second surprise was the relative size of the holes, the inlet for the primary air (doghouse and air wash) is about 1x2.5", while the secondary inlet is about 3x6". This does not necessarily correspond to much higher airflow since there may be more restrictions in the secondary piping, but I was not expecting this large a difference.
The slider has two separate plates which can easily be removed and for those interested in "tuning" their stove, these plates could easily be fabricated to give a custom air mix.
The full closed position is limited by two bolts which stop the slider moving any further, leaving an extra 3/8" of travel possible if the bolts are removed before the slider will stop against the end of the housing. Using an insence stick, it was very easy to confirm that removing the bolts allowed complete closure of the air supply (see pics).
I am interested in completely closing the air supply for two reasons, in case of an overfire or chimney fire, but mostly to eliminate the significant downdraft I experience when the stove is not in use, which is 5 days a week in Winter, and all through the rest of the year. I didn't want to lose the current stop position, but wanted an easy way to override if necessary.
Comments, thoughts, suggestions. Pictures to follow.
TE
Firstly, the air control consists of two sliding plates, each with a rectangular hole, pushed up with springs against matching inlet holes on the underside of the stove. What I noticed first was that contrary to my original thought, the relative proportion of each air supply does not change with slider position. There is a triangular hole on the primary air inlet, but the matching hole on the slider is rectangular and smaller than the triangle, so the resulting opening will always be a rectangle.
My second surprise was the relative size of the holes, the inlet for the primary air (doghouse and air wash) is about 1x2.5", while the secondary inlet is about 3x6". This does not necessarily correspond to much higher airflow since there may be more restrictions in the secondary piping, but I was not expecting this large a difference.
The slider has two separate plates which can easily be removed and for those interested in "tuning" their stove, these plates could easily be fabricated to give a custom air mix.
The full closed position is limited by two bolts which stop the slider moving any further, leaving an extra 3/8" of travel possible if the bolts are removed before the slider will stop against the end of the housing. Using an insence stick, it was very easy to confirm that removing the bolts allowed complete closure of the air supply (see pics).
I am interested in completely closing the air supply for two reasons, in case of an overfire or chimney fire, but mostly to eliminate the significant downdraft I experience when the stove is not in use, which is 5 days a week in Winter, and all through the rest of the year. I didn't want to lose the current stop position, but wanted an easy way to override if necessary.
Comments, thoughts, suggestions. Pictures to follow.
TE
