Draft settings for a Burnham V908A w/Beckett CF1400

STEVEusaPA

Hey Wallies, have a new customer clean out tomorrow with the above mentioned set up. I downloaded both the boiler manual and the Beckett manual, but neither one tells me what number to set draft.
The boiler manual says check the burner manual, the burner manual says check the boiler manual. I have all the other settings-head, low/high air band, low/high pump pressure, nozzle, etc., just not draft. The only thing the Beckett manual states is "...typically +.01 at the breech".
I'm expecting to spend alot of time with this as the owner mentioned a number of other people took a crack at it, which to me means, wrong nozzle, wrong air settings, wrong draft.
If anyone has any insight I'd greatly appreciate it.
Thanks
Steve
Edit: Giving the boiler manual another read I missed the first table, which looks like .35wc pressure in firebox and +.10 at the breech, which seems high. I'll probably give US Boiler a call tomorrow

EBEBRATT-Ed

I was told by 1 boiler mfg that running positive pressure over the fire results in the best efficiency but they admitted that the gain in efficiency is negligeable .
I would go with the +.01 or something close to that at the breeching but I wouldn't dwell on it then adjust the burner until you get good #s

Steamhead

That's pretty typical for pressure-fired boilers. I checked the manual and didn't see a procedure listed. On at least one other make, they have you open the breech damper, set the burner for 12% CO2, then close the breech damper until you get +1 at the breech before the damper. This will give a CO2 of 12.5-12.9 % in my experience. Always do a smoke test after closing the breech damper.

STEVEusaPA

Thanks for your comments gentlemen!