setting boiler draft

[hvac17011]

working on a commercial weil mcclain boiler. it is to be set at positive .2 at breech damper. my question is what should the reading on smoke pipe between breech and draft regulator be set at(what should i set draft regulator at??)

[powerhead]

H,
I may be misreading you post, but,
Your question implies that you are not a burner tech (neither am I).
If you have to ask a qustion like that than you should not make any adjustments to the burner or breeching, could be very dangerous.

If your legit, try posting over
here (http://www.oiltechtalk.com/discuss/)

powerhead

[Edited by powerhead on 01-17-2006 at 11:20 AM]

[hvacpope]

Originally posted by hvac17011
working on a commercial weil mcclain boiler. it is to be set at positive .2 at breech damper. my question is what should the reading on smoke pipe between breech and draft regulator be set at(what should i set draft regulator at??)

size and fuel type?

[beenthere]

You'll find that info in the install manual.

Keep in mind, that after the breech damper, the flue pipe draft is no different then a neg pressure boiler.

[onetime]

Go to the Bacharch website they have alot of combustion testing info

[gonefishing]

Like onetime said.

You have to look at the whole picture when you start
adjusting air/fuel ratios on burners. It's the difference
between a clean flame, and CO.

You need to look at stack temp, and combustion gas
composition while making adjustments. Get the whole
picture BEFORE you make adjustments.

Regards......

[boilernazi28]

draft at damper breeching ,,taken at 1/4 in plug should be .01 positive ,in stack ideally should be .04 negative, positive pressure should be abtained by damper closure ,,,,very inportant CHECK overfire pressure dont exceed factory recomendations