Homeowner Q: firing rate of gas boiler

Dale

While your gas meter test seems pretty close I can think of a few things to check. First, are you on #2pound gas? If so the actual amt. would be fine, second what is the manifold pressure, does it match nameplate? Are you in Denver or someplace above 2000ft where gas appliances should be DErated? Did you use the largest (most accurate) test dial on the meter, did you use a stopwatch? Did the valve you chose for replacement have the flow capacity to match the boiler input? What is the line pressure to the boiler before the valve, is it less that 6" or so?

Duane

Firing rate of gas boiler

I just replaced the Honeywell gas valve in my Burnham IN4 boiler, having had a no-pilot situation that a new thermocouple failed to rectify. It works fine now.

I decided now would be the time to check the gas usage versus the rating on the unit. I timed the gas meter according to the Burnham manual instructions. I found that the apparent firing rate is only about 85-90% of the rating listed in the manual for my boiler.

According to my calculations done last year when I bought the house, the boiler is slightly oversized, but not enough to worry about; the next size down unit wouldn't have been large enough.

Should I leave well enough alone ? What is the penalty if any if my gas firing rate is less than the nameplate value ? Is there any physical evidence left if the boiler was down-fired by a previous owner ? I have no written evidence of it. I should mention that the system works very well after I worked it over with the help of Dan's book, correcting just about every "error" listed.

Thanks.