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Interesting Biasi scenario, older B-3 with Beckett NX
Just curious because I haven't worked on a lot of them and found no info or tech bulletins. We have one at the school and it seems the boiler rating info is wrong, it stated for a Beckett NX in a B-3 use a .55 nozzle at 180PSI, the mas boiler input is .55, that over fires the boiler. As far as I can tell we've always had issues with it, I decided to take it on and found not only was it impossible to get a zero smoke, the CO AF was 374PPM. The chamber had no liner so I start to suspect this is at least partly causing my CO and poor flame issues ( cold fire, impingement), then I found that in the boiler instructions there is listed a chamber liner but no reference as to installing it. Found new boiler literature that now states in a B-3 run a .40 nozzle at 150PSI to get the .55. Only problem is I am not crazy about running anything below a .65 with #2 fuel.
I settled on the .50 at 120PSI and with a new liner and the head set properly I'm happy to report CO AF is 40PPM and steady and the rest is perfect.
Just curious what others have found over the years and if there ever was a tech bulletin, etc regarding this?