Cat dial question

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reaperman1

Member
Aug 7, 2022
88
Minnesota
I’m in the learning stages of my new BK boxer. The dial for the cat is pretty self explanatory. However, the dial turns way past the low setting, almost making a full circle. On the highest setting the dial stops in the 6:00 position and the low setting is counter clockwise to the 12:00 position. For some reason the dial is able to go way beyond the 12 position before it hits a hard stop where it almost makes a 360 degree swing. The dial is tight and reactive when turned. I’m just curious if there is a reason it’s able to go way past the low setting.
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Ashful

Minister of Fire
Mar 7, 2012
18,062
Philadelphia
Not sure of the reason, but yes... this is something we've all run across, it is "normal". The useable range on most models is about 1/4 of the circle, from wide open to completely shut. You can hear the flapper close when backing off from high setting, and the position where that happens on a cold stove is "dead shut", no point in ever turning lower than that mark.
 

reaperman1

Member
Aug 7, 2022
88
Minnesota
Not sure of the reason, but yes... this is something we've all run across, it is "normal". The useable range on most models is about 1/4 of the circle, from wide open to completely shut. You can hear the flapper close when backing off from high setting, and the position where that happens on a cold stove is "dead shut", no point in ever turning lower than that mark.
Thank you, I hear the flap around the 2 o'clock position so I penciled a line at that spot. So if I understand correctly, my range would be 6 o'clock wide open to 2 o'clock closed?
 

Ashful

Minister of Fire
Mar 7, 2012
18,062
Philadelphia
Thank you, I hear the flap around the 2 o'clock position so I penciled a line at that spot. So if I understand correctly, my range would be 6 o'clock wide open to 2 o'clock closed?
Exactly. In fact, once warm you'll notice the flapper probably closes between 2:30 and 3 o'clock, depending on the temperature of the stove. The relationship between that flapper and your knob is controlled by a coiled bimetallic spring, such that the flapper will open and close as the stove heats and cools, to maintain a more consistent temperature as the fuel goes thru its own phases of combustion.

It's real handy to start with some masking tape on the dial, and writing down the total burn times for various knob positions. Once you have that mapped out a little, you can mark your dial permanently with your 12-hour and 24-hour positions, in addition to this dead-cold position. The Boxer is small enough that your "dead cold" and 24-hour positions may be the same, and you may choose to mark 6, 12, and 18 hours instead of my 12 and 24. My dead cold position is well over 30 hours, maybe as much as 36 hours, I've honestly never watched it close enough to know precisely.