Page 1 of 1

Chain length adjustment for bimetallic air inlet flapper?

Posted: Fri. Sep. 01, 2017 9:02 pm
by lsayre
So far I've only burned wood in it, but in case I try some coal this winter, I need to get my air inlet chain set right on the DS ComfortMax.

Presently, when the stove is completely cold, and the bimetal control dial is turned all the way to its lowest temperature setting, the air inlet flapper cover is still open about an eight of an inch or a bit more. Does that sound right, or do I need to add more chain to it (lengthen the chain)?

Re: Chain length adjustment for bimetallic air inlet flapper?

Posted: Fri. Sep. 01, 2017 9:40 pm
by franco b
I would leave it. Just closed when stove cold and set at lowest heat setting is about right, but I think you are in the ballpark. It still gives you a lot of setting room.

Re: Chain length adjustment for bimetallic air inlet flapper?

Posted: Sat. Sep. 02, 2017 7:39 am
by lsayre
franco b wrote:I would leave it. Just closed when stove cold and set at lowest heat setting is about right, but I think you are in the ballpark. It still gives you a lot of setting room.
Thanks! to add chain I'd probably have to buy a new chain, as the present one has no spare beads (links) available.

Re: Chain length adjustment for bimetallic air inlet flapper?

Posted: Sat. Sep. 02, 2017 8:25 am
by freetown fred
A big DITTO Larry! :)
franco b wrote:I would leave it. Just closed when stove cold and set at lowest heat setting is about right, but I think you are in the ballpark. It still gives you a lot of setting room.

Re: Chain length adjustment for bimetallic air inlet flapper?

Posted: Sat. Sep. 02, 2017 8:33 am
by lsayre
So the consensus (of two) is that even if it doesn't close fully when room temperature cold, but is about 3/16" open, it is OK as is. Correct?

Re: Chain length adjustment for bimetallic air inlet flapper?

Posted: Sat. Sep. 02, 2017 9:36 am
by KingCoal
yes, when my stove is hooked up but not running i release the chain altogether, though it doesn't matter that much as my chimney will still draw thru the secondaries.

when i use the stove i wait to get very precise about the chain length until the house is up to comfort level, i have a settled fire under desired draft pressure then, if i want say 400* at the stove hot spot i set the chain to have the damper at about 1/16th when the dial is at 2. that way i can shut it completely or turn it up as far as i want.

i'm glad to hear you may use your stove for coal some this yr. it will be neat to hear how it acts.

steve

Re: Chain length adjustment for bimetallic air inlet flapper?

Posted: Sat. Sep. 02, 2017 11:40 am
by franco b
lsayre wrote:So the consensus (of two) is that even if it doesn't close fully when room temperature cold, but is about 3/16" open, it is OK as is. Correct?
Yes. As long as there is room to go higher or lower when the stove is hot. You will see it rapidly closes all the way as the stove warms up, and you will have to raise the setting.

Re: Chain length adjustment for bimetallic air inlet flapper?

Posted: Mon. Sep. 04, 2017 11:30 am
by lsayre
I spoke with DS Machine today (they called me in response to my online inquiry) about this and a few other subjects, after I measured my actual opening of the inlet cover at 3/8" (vs 3/16"). They thought that it should still work as is, but said that I could lengthen the chain by a bead or perhaps two if I desire. They said the ideal air inlet opening gap when the stove is at room temperature should be about 1/8".

Then we moved on to pea vs. nut, and their opinion was that nut will offer better overall performance, and greatly lessen any tendency to experience out-fires.

Then I was informed that due to new regulations (EPA I presume) the ComfortMax 75 is no longer being offered as a dual purpose wood/coal stove, but rather must now be sold as a coal only stove.

Overall a great talk, and they were completely willing to help and answer these and any other questions I might have needed answers to. I tip my hat to this company!

Re: Chain length adjustment for bimetallic air inlet flapper?

Posted: Fri. Nov. 03, 2017 1:03 pm
by lsayre
I finally got around to lengthening the ComfortMax's chain today. Fortunately there were two spare beads at the flapper end of the chain, so I didn't need to go out and buy a new one. I added in only one more bead, and now the air inlet flapper just touches home (fully closed) as the dial indicator hits its lowest set-point. No theoretically ideal 1/8" gap, but much better than it was. The chain is still taunt when the flapper is closed fully. This with a room temperature stove. Amazing how just a single bead changed things as much as it did. It closed a roughly 5/16" to 3/8" gap down to zero gap.

Re: Chain length adjustment for bimetallic air inlet flapper?

Posted: Sat. Nov. 04, 2017 11:50 am
by KingCoal
hmmm, i never thought to look at the top end of the chain for extra beads but then, i usually have 4 or so under the adjuster at the low end when the stove is running.

happy burning this yr,
steve