Boiler does not raise pressure

bostonsteam

It is a Mcdonell-Miller 47-2, Mechanical Water Feeder w/ #2 Switch (LWCO Function). At the bottom left there is an electronic device that has two lights: red when water is missing and green when water is ok. I think.

ChrisJ

I didn't notice the style float LWCO it is.

I'll be honest, I don't know how those act in regards to adding water. Perhaps they maintain the proper water level?

vaporvac

bostonsteam said:

At the bottom left there is an electronic device that has two lights: red when water is missing and green when water is ok. I think.

That is the probe LWCO that doesn't require a blowdown, just yearly maintenance and occasionally checking that it works. Interesting that your boiler has both.

Regarding you HW loop... generally the 30% that is alreading included in the boiler's sq ft rating is adequate for heating that water. Do you know how many BTUs your HW loop uses? (However, given the huge oversizing of you boiler this probably is moot.) Stick to the venting for now and find another Steam person. C.

Furnacelady

The higher the pressure the less BTU's you get out of steam and it is considerly less. You do not want higher pressure. Fine tuning the return vents and radiators is a timing issue. Steam travels fast, but air gets in it's way. First you want all end of mains (EOM) to get hot at the same time, if every thing was equal, but it's not. The longest run you want the EOM to be hot at the same time as the other EOM. Bigger or more vents (manifold of vents) on the longest EOM run accomplishes that. Next is timing steam to the radiators, closest ones get smaller vents, further get larger vent. It's all in the timing and using helpers at the EOM and radiators.

Larry_52

Furnacelady said:

The higher the pressure the less BTU's you get out of steam and it is considerly less.

That is not true, the more pressure the more enthalpy of saturated steam. It is the system that gets less btu's with higher pressure due to its context.