TRV

DWood

TRV's would be a fine way to "balance" your one pipe steam building. Most manufacturers, including Danfoss, have a one pipe steam valve that is screwed into the vent hole on the cast iron radiation. For the TRV's to function correctly, the one pipe steam system must cycle down to 0 psi pressure at least once an hour to allow air to get back into the system. The Danfoss 1 ps valve has a built in vacuum breaker to allow air back into the system even if the operator is satisfied and the seat a disk are closed.
For proper operation the system should be run on oz. of pressure, not pounds. 1 psg is more than enough operate most buildings.
The comment about "knowing" your system is valid.
Good luck.
DWood

D.Volpone

One pipe steam in an apartment complex, some areas hot, some areas comfortable, some cold. All air vents are working and of the unadjustable bleed rate. My question is to balance this system, do I change the air vents or install TRV? If the answer is a TRV, what kind? All the TRV I see are for 2 pipe steam
Thanks in advance

Earthfire

one pipe

One pipe is a good heating system when operating properly. Go to books and more and buy the books . They will give you an understanding of how your system is supposed to function. Your question sounds like " my car is running hot, I opened all the windows should I change the gas pedal?" the answer is DEPENDS ! After understanding your system, verifying that all the piping and system components are functioning properly or not you can make the decision whether you want to tackle the problem yourself or have a pro handle it. Parts swapping may fix the problem MAYBE!!. as Dirty Harry used to say "Feelin Lucky" KNOWLEDGE IS POWER!!!!!

Unknown

here's one

http://www.gspn.com/macon/opsk_b.html