Steam Trap ID Help

Old_McDonald

Does anyone know what kind of steam trap this is, if it is indeed a steam trap? It's on the return side of a radiator from a two-pipe system. The only markings on it are the logo for "P&C Co", which I can't find in any of my steam books. The house was built in 1839 and has a 100+ year old two-pipe steam system. Most of the rads have air vents which I think may have been added sometime in the last 50 years, but I'm not sure. About half of the rads are slow to heat. They're all pretty noisy. I'm thinking I need to consider replacing or refurbishing the "traps" on the returns. Thanks in advance for any knowledge you may share on this.

Steamhead

Where

is this system located?



That unit might be an "impulse valve"- see the Donnelly system in chapter 15 of Lost Art.

Old_McDonald

Donnelly System

I think you're right Steamhead about it being a Donnelly System. Thanks!



If by "where" you mean what part of the country, this is near Pittsburgh, PA. I'm guessing early 1900s for the current system. Each of 22 rads has one of these on the discharge. It's a pure gravity return.



So, now the question becomes is there some kind of maintenance I should try to do on these things? And should I remove the air vents that someone has placed on each radiator? There is a main air vent in the basement right before the return drops into the boiler...it seems to be working.



Thanks again.

Steamhead

It's possible

some of the check valves in these units are stuck- go thru and make sure they all work.



And get rid of those radiator vents. Upgrade the main and dry return vents too.

Old_McDonald

Impulse check valves

I'll take your advice Steamhead and remove those air valves, upgrade the return vents, and see what I can do to figure out if the impulse valves are stuck. Thanks for the help.