Residential ONE PIPE STEAM SYSTEM

steaming

Dear KC, Fred and the Wall:
Thank you for your reviews, I posted a variation of this issue in August.
I am going to attempt to write a more concise question(s) regarding my one pipe steam system. Taking your advise I've included the attached pictures.
I have a Weil Mclean model EG-50-PI, 175 btu's natural gas steam boiler installed August 1985.
This is well insulated residential 3 story building with a 30' by 40' footprint. There are 12 radiators of varied number fins with Hoffman 40's and Maid-o-Mist air valves on 4 radiators furthest from the boiler. In the basement are two- 2" parallel mains about 30' (plus) feet which run along the east and west sides of the building.
The second and third floors are not getting steam, or the balance is wacked, some risers get hot while others are cold.
I replaced the Honeywell Pressure Limit control 20 PSI PA404A1009 and the Weil Mclean steam pressure gauge. I have thoroughly cleaned the pigtail, however the new gauge does not register. The boiler cycles on frequently, warming the first floor shutting down the thermostat. Without a gauge reading its difficult to set the Pressure Limit Control. There is no hiss of air venting in the basement. I've checked for leaks in the boiler and the floor return pipes, which checked out OK. The floor return pipes were replace 10 years ago. I have drain the boiler, but have never thoroughly washed it, for of fear of the mess.
KC, Fred and the Wall, would you kindly revisit my issues?
Thank you.
Terrence
Sunnyside, Queens, NY

Dave in QCA

I'm didn't see this post before now, and I see no one has jumped on. I don't recall your previous posts, so I'm going to give it a try here.

First, you indicate that the boiler frequently cycles on but shuts off by the thermostat. It seems that there is a strong possibility that your thermostat is not set for steam, and thus is producing lots of short cycles, which would be great for forced air. What kind of thermostat do you have? Can you take a picture of it. If it is a round Honeywell type, please pull of the cover and take a picture of it that way too.

The second very obvious thing is that your main vents are WAY to small. I know that most of the folks on here do not like Hoffman 75s, but we think they work great here in the Quad Cities. I would install at least one Hoffman 75 at each main, or one Gorton #2. If all of your mains in the basement are uninsulated like the one in the picture, a Gorton 2 should work fine. I see problems with Gortons doing much good unless the piping cools down.

Hoffman #40 are good slow vents and should assist in evening out your system. You mention that you have Maid-O-Mist vents in some places. What size orifices do you have in them and where are these vents installed. Do these radiators get hot?

Boiler and piping all looks good to me, it should not be an issue to get your heat evened out.

Jamie Hall

I think I recall the earlier thread... maybe not.

I have no problem with Hoffman 75s. One of my two lonely vents is a Hoffman 75 (the other is a Gorton #2, both on the same antler. Seems to work fine). Although more venting often helps, I'm not sure that what I'm reading suggests that.

I can think of two possibilities, though. First, as Dave suggests, is the thermostat set right for steam? One cycle per hour, or if it is the anticipator sort, with a nice long delay on the anticipator? If not, that could cause part of the trouble. The other part, though, could come from the location of the thermostat: is the radiator in that room one of the more energetic ones? If so, it's quite possible that the thermostat -- being no smarter than most -- is controlling the temperature in that room nicely enough, but the room itself is heating up too fast. Can you try calming that radiator down? Or turning it off completely (turn the vent upside down -- don't use the valve). Try that and see what happens.

You want the radiators on the first floor -- especially the one(s) near the thermostat) to be nice and slow, and the ones upstairs or in other rooms which need more heat to be faster.

Fred

Yes, he reposted and is getting assistance on this thread:
http://forum.heatinghelp.com/discussion/155243/steam-heat-weil-mclain-boiler#latest