Wood boiler draft?

[Eastcoast]

I have a Kerr tw2000 wood boiler and a oil boiler. on my wood boiler I have a double aquastat with high limit and low limit and a single aquastat limit control for circulator ok pump and on my oil boiler I have a triple aquastat with high limit low limit and differential knob I know my draft shuts at the low limit on my wood boiler but what determines at what temperature the drafts opens again? And can I change this setting? Thanks

 

[maple1]

Follow the wires from the draft motor to the stat controlling it. Should be able to adjust yes. If u can post a pic of it that would help. Lots of different possible controls with these things. Usually draft door is controlled by a single stat, on top. With an adjusting wheel in it.

 

[Eastcoast]

Here's my set up, I'm wondering if maybe my triple aquastat beside the oil boiler with the differential controls when my draft opens on my wood boiler. I know the draft closes at my lo setting on the wood boiler which is 170 right now so if it closes at 170 and my differential on the triple aquastat is 15 will it let the temp drop to 155 then open the draft and heat back up to 170?

 

[maple1]

Ya I dont think I'll be much more help. That's controlled a bit different than what I'm remembering on my old one. If I was there I would just follow wires and spin dials and see what each one did.

 

[Eastcoast]

Ya I think that's what I'm going to have to do! my wood boiler draft is shutting at my lo limit but I'm going to play with the diff dial on the triple aquastat and see if that's what determines what temperature it opens. Thanks anyways!

 

[Eastcoast]

Well I started twisting dials and trying stuff and so far what I figured out is on my oil boiler the low limit turns the burner on and it shut off at my hi limit plus diff I have it set to lo-150 hi-170 diff 10 so it turns on at 150 and shuts off at 180 does this seems normal? And on my wood boiler the hi limit seems to be just a safety limit and my lo limit shuts my draft just didn't figure out the temp the drafts opens back up yet. Just thinking that maybe the triple aquastat on my oil boiler with the diff dial maybe controls it so if it's at 10 where I got it now maybe it will let the temp drop 10 below my lo limit just seems to be backwards from the oil boiler. Any suggestions?

 

[maple1]

The low limit working your draft might have a built in non adjustable differential. I would bet.

Like said before a lot of these adjustments comes down to how good it is or isn't heating your house now, or how good the two units are playing together now or aren't. Still haven't heard you say on that, I dont think. I would keep my oil unit as low as possible as long as it can still heat how you need it to.

 

[Eastcoast]

I think you may be correct I think It might be on a non adjustable differential for my draft! And as far as how good it's heating my house now it seems to be doing fine just trying to get the best efficiency out of it. I have my wood boiler at hi-200 and low-180 right now I'm wonder if I go down to 160 with the low will it created more creosote in my stove? I know I will save a bit on wood but I don't want to create a creosote problem either.

 

[maple1]

Personally I would not go higher than 180 high on a boiler. Creosote issues are more apt to be due to wet wood and/or loading too full and/or too often for the heat demand.

 

[Eastcoast]

Thanks I think my problem with the creosote was over loading with to much wood