chimney size selkirk 640/zc40, replacing with hearthstone wfp 75

[avionator]

Hi,

I am looking to replace my current zc (Selkirk 640/zc40) with the Hearthstone wfp 75. The Hearthstone specs a 6 inch chimney. How to i measure the current chimney on my current ZC? I don't have direct access to the pipe itself unless i get my 32 foot ladder out. The actual exit from inside the fireplace measures 8 inches in diameter. Does this mean i have an 8 inch chimney? Multiple sources online seem to indicate that this unit should have a 6 inch pipe. Would the firebox exit at 8 inches reduce to a 6 inch pipe? That doesn't feel quite right to me...

 

[avionator]

So i just realized i could open the flue and peak directly up the chimney. It definitly reduces the ID (though i can't reach to measure it). So I presume it's safe to say this is a 6 inch ID pipe.

 

[bholler]

So i just realized i could open the flue and peak directly up the chimney. It definitly reduces the ID (though i can't reach to measure it). So I presume it's safe to say this is a 6 inch ID pipe.

Your chimney pipe also needs to be specified for use with the new fireplace. Just the right size is not enough

 

[begreen]

It looks like there is a chance that the existing chimney pipe will work. It will be necessary to identify the exact brand/model of chimney pipe and to verify that it is still in very good condition. There may be a label still on the pipe inside the chase. The Selkirk fireplace required Supervent's (Model SC, JM, & ALT) or Selkirk's Metalbestos(Model SS, & CF) chimney pipe. The Hearthstone's manual lists some of these as acceptable for the fireplace. If there is a good match, a new anchor plate may be required.