[an error occurred while processing this directive]
Posted by Doug Criner on October 19, 2008 at 16:10:06:
In Reply to: Excess Air - too high posted by Doug Criner on October 16, 2008 at 18:28:18:
Well, I've made some progress.
I adjusted the barometric dampers so that they swing about 50% open with the burner on, thus reducing the boiler draft.
I somewhat reduced the primary air adjustment on the burner. (But I still have good-looking blue flames.)
Then I duct taped over several openings in the burner ductwork, thus reducing secondary air being sucked into the firebox.
I'm now measuring about 100% excess air - which gives an improved boiler efficiency of around 81%. I will try to do some more tuning when the weather turns colder. I think I should be able to reduce the excess air down to 50%, or so, which would improve the efficiency even more. That will be very acceptable to me for a boiler that is nearly 60 years old.
Doug