Defiant 1975 Damper Help

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MikeVT

New Member
Dec 20, 2020
2
VT
Been a reader for about 3 years and have learned great things on here, as a first time stove owner. I’m now at the point where I had to register to ask for help, so thanks in advance all!

I have a VC Defiant 1975 (non-cat) stove that came with the house. I’ve burned 2-3 cords per year for the last 3 winters (currently this is the 4th winter). The problem I’m experiencing: the damper will not close all the way because it is physically hitting the part of the stove top that it’s intended to rest against to create the seal when fully closed. This problem has progressively worsened...1st year = only happened ~550+ F stove top temp, now it happens at ~325+ F stove top temp (year 2-3 were between the two temps). Obviously the metal is expanding with heat and the “cold temp clearance” ceases to exist above X temp, which physically prevents the damper from getting to the full closed position (and I can only manually hold the damper at that point, otherwise if I let go it just gravity-falls back to the full open position).

Pic 1: Overview to give perspective on what I’m talking about
Pic 2: Left side of damper with sufficient clearance
Pic 3: Right side of damper with insufficient clearance

My thoughts are:

1. The damper is clearly not parallel to the part of the stove it’s supposed to rest against in the closed position; so fix is level it (how?)
2. Don’t mess with damper and just file down the area that the right side of damper is hitting when at 350F+, to create the same clearance as the left side

The best answer is probably “level the damper,” but not sure how to go about that. However, is the filing idea sufficient/safe? I’m perplexed as to why the problem has progressively worsened over the years and not just maintained (I could live with damper always closing below 550F temp). I certainly don’t want to start doing irreversible modifications without making sure its a sound gameplan. Please let me know if any other info/pics are needed to determine the best course of action. Thanks!

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whenever i hear of dampers that don't close flush, i think of warpage. doesn't have to be much, but over the years it increases. perhaps creosote building up and throwing it off true.
 
Now that I look closer, the fireback is warped on the right side, so not sitting flush, which is in turn making the right side of the damper sit high. I’ve been wrestling with the fireback for a bit, but can’t seem to get it wedged into the right spot.

In the attached pic, the red arrow points to the bottom right of the upper fireback, the blue arrow points to the lower fireback lip that the upper is supposed to be “hooked” over (e.g. in front of from this perspective), and green circled area is where the upper fireback is resting on the lower fireback “lip”, which is ultimately causing theright end to be too high.

If I could get the damper out, I could easily lift the upper fireback out (and maybe replace?), but don’t see how I can do that without doing some significant disassembly. Recommendations?

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sometimes you can cut back the damper gasket at the gap area and install a thicker gasket to tied you over for the winter. the early VC stoves can be broken down and reassembled in two days provided you have everything you need. might wait till spring to do that.

in the lower areas you might fill in with furnace cement for now.