Long time lurker, first time poster.
I'm the new homeowner of a 1-pipe steam system in Western MA. My boiler is a Dunkirk psb-5d (https://www.plumbersstock.com/dunkirk-psb5d-cast-iron-natural-gas-boiler.html
), approx 25 years old (per previous homeowner).
My problem is as follows: Water is exiting the system, such that in very cold weather periods as we've been having, I need to add water every 4-5 days or so, else the auto-feed comes on. Main and radiator vents are spitting out steam after they should've shut tight, i.e., after the dry air's been expelled from the system.
I've replace several of the rad vents with the appropriately sized maid-o-mist or gorton vents, to the best of my ability, though some retain the adjustable vents the previous homeowner installed just prior to my purchase. I replaced the clogged-to-death Hoffman main vents on the 2 tapped mains last year with Maid-o-Mist #1's. On one of the two main vents the housing has cracked, from what I'm assuming is excess pressure while the float bravely held, while the float on the other has on the other had failed, meaning that steam blows out of that one.
At first I thought maybe I've got a crack in the boiler itself, which I have yet to test by flooding the boiler and looking for puddles. But, I'm more inclined to think, and asking you guys for your input on whether there's too much pressure in the system. That is, am I burning gas to heat water that's already been heated enough to create enough psis/steam to heat my house, and I'm therefore burning gas & creating excess pressure, leading to waste and busted vents?
So if this is pressure, time to troubleshoot the pressuretrol. My boilder has one of those 30 psi gauges, which I know is useless other than for meeting code, so that's not telling me much. Per the picture, I've got a Honeywell pressuretrol mounted onto the boiler jacket, with the pigtail coming off the sight-glass. Most folks I see on here have their pigtail dangling in the air, easily accessible/removable. Pic: http://imgur.com/a/KZfBV
I think I need to remove the pressuretrol and pigtail and clean or replace the pigtail so that the pressuretrol registers the correct pressure within the system and cycles off accordingly, but the pigtail is mounted in such a way that simply twisting it off isn't as straightforward as if it were mounted perpendicular from the boiler.
Let me know your thoughts, what I'm missing or tell me I'm way off. Thanks.