High pressure, any ideas

malex

This is my first heating season in this house with a one pipe steam system. I have had the pressure in my boiler hover around 10psi whenever the thermostat calls for heat. It goes down slowly to 0 when heat is turned off. The cut-in was always set to .5 (lowest) and I dialed down the diff to 1 (it was set to 3) but nothing changed. I just cleaned the pig tail and there was no change. I made sure the pressuretrol was perfectly level and that the pigtail curled towards the boiler so that the pressuretrol does not tilt as the pigtail gets hot and may change shape.



The pressuretrol looks brand new but it seems this is the only remaining culprit. Does anyone have any other ideas to try before I switch it out?



The main vent are old and does not seem to be venting well and I am ordering new vents but this would not explain why the preasuretrol does not cut off as the pressure goes past 1.5psi, right?



Thanks