Posted by mike on February 20, 2000 at 18:34:34:
In Reply to: Re: boiler posted by Rick Bullard on February 11, 2000 at 09:46:24:
: : Today we had a boiler that had the o2 go from 4.2 to 9.2,also the sides of the boiler started pulsating. it was pulling about 40000. We have Preferred Instruments Controls.Any Help ?
: The increase in O2 indicates an increase in excess air. I'd check the FD and/or ID fan controllers or the oxygen trim controller if you have O2 trim. The furnace was pulsating from an excessive amount of fuel-gas being carried through it.
also check your safeties on feed water heater to make sure they are not drawing in air! thsi is were O2 might be coming in!