Defiant encore secondary air thermostat question

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ray milosh

Member
Nov 30, 2012
20
I just rebuilt a mid 80s defiant encore model 2140. I installed a new secondary air thermostat according to the directions., The arm that attaches to the coil starts at the 4 o’clock position allowing only a tiny amount of air in the secondary air inlet. As the stove heated, the spring rotated clockwise further closing the inlet until it got to the 8 o’clock position and stopped there. That can’t be right.
I’m wondering if the spring is on backwards from the factory...Like it should start at the 4 o’clock position and move counterclockwise up to the 2 o’clock position. I assume it should open after the damper is closed and the secondary air inlet thermostat reaches, I dunno, 500° or so, right? Thoughts?
 
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The secondary probe is designed to close off the gate once it heats up, so yeah. I think you're good.
 
The secondary probe is designed to close off the gate once it heats up, so yeah. I think you're good.
Defiant4, Thank you for the reply, but... Wait, what?
I think there might be something I have completely misunderstood. The way I have understood it, The secondary air gate would stay closed when the stove is cold and it wouldn’t open until the catalyst got hot and then the secondary air would be allowed in to provide oxygen to reignite the wood gas just as it gets to the catalyst. And you are saying that the secondary air gate should be open just a little when the stove is cold and completely closed when the stove is hot? Could you point me to a document that explains how this works or explain it to me, please? I’m definitely confused.
 
Last night, I heated the original thermostat that I had removed and replaced. It, too, starts at the 4 o’clock position and rotates clockwise.
I can only assume that the spring rotates around to the eight or 9 o’clock position which would open the vent as the stove reaches 500° Or so. It just has too. What would be the point in having a secondary air vent that starts almost closed and then closes ?