Should the sight glass of a steam boiler always be within the recommended range? Or only when firing?

Question

We just had a new steam boiler installed and it is working great; all radiators are hot when the heat turns on etc.

One thing I noticed though is that the site glass for the water level reads too high when the boiler is off:

notice the water level is above even being visible in the sight glass.

When running the water level is within the recommended range:

I've tried draining the boiler when it is off to bring the water level down, but when the boiler fires up, the water level goes lower, hovering around the lowest acceptable level. This triggers the auto-feeder, and I end up back where I started.

So the question is, is this ok? Or should I try to tweak the auto-feeder?

FWIW, it is a Utica pg-150 which seems to have plenty of capacity for our 1600 sqft home, and is of a similar capacity to the one another heating and cooling company quoted.

Answer 1

I talked to the guy who originally installed the boiler and he suggested that the pressure was probably a bit high (was set to 1.5 PSI) for our house; if the pressure is too high, then more steam than the radiators can handle is sent out at a time, and therefor the steam doesn't condense back to water at the radiators at first, so the water level gets low and the auto feeder turns on.

I turned down the pressure to just below 1 PSI and it seems to have done the trick, the water level on the site glass doesn't go down as far while the boiler is operating. Also, according to this article, steam heat pressure really does't need to be high at all, so there is no worry on my end about turning it down.

In order to turn down the pressure I adjusted the screw at the top of the box next to the pressure gauge: