30 psi steam pressure one pipe system

Uwe

I have a one pipe steam heat system. Boiler is made by Crown, Bermuda series. Before summer I drained the water out of the system and filled it up again this week. Although the pressure limit is set to 1 psi the steam pressure goes up to 30 psi when the boiler fires. Once it reaches 30 psi the pressure goes down slowly. When I blow down or drain the low water cut off after one cycle the water is pitch black. The pressure relief valves are sized for 15 psi but they do not actuate. I assume something is clogged here. Does anybody know where to check ? Thanks.

Unknown

Check the pressure gage first

I try to keep the gage out of direct steam , usually after a pigtail . It'll last much longer . But first make sure there really is no pressure in the boiler by turning the power off and letting it sit for a few minutes . Better to be safe .

Unknown

This system

This system needs service before it is run.

The controls might be plugged up and not working, which is dangerous.

Noel