Trane Vapor System?

FitterFreds

Received a call from a classmate of mine and he had some issues with his old steam system. We wondered around the house a bit and at each radiator they had a Trane valve with a handle extension. I would call it a throttle valve. With a dial position indicator. All work but one. There are no Traps on the radiators! Two pipe, one in one out. In the basement it has on it what looks like a Direct Return trap. The only thing is it has an air vent out the top of it ( Dole 3/4" could not get the no. off of it ). That was the only air vent that I could see on the system. The main reason that he called was that his system flooded all the way up to 2nd floor. The pipes look OK less one return line that is rotted out. Can you rebuild McDonald Miller 101 water feeder? and the MM 67 LWCO? I'll try and get some pics up, but really would like to know more about those Trane valves and Return trap. Is this a Vapor system?

gerry gill

its very possible

that the feeder is okay and was doing what it was asked to do..thats not to say it may not be bad, but if the 67 hasn't been taken apart and cleaned like its supposed to be each year, it may have sent the feed signal and got stuck in muck..has your buddy done the weekly blowdown?

Steamhead

Look at Chapter 15

of "The Lost Art of Steam Heating". I bet you find that Trane Vapor system on pages 257 and 258.



The Dole vent is almost certainly too small for this system. Use a Gorton #2- it's the biggest vent made today.

FitterFreds

...and then

Gentlemen, thank you for your responses. @Gill, when I depress the manual fill button on the 101, it has a hard time " springing " back up. I'll suggest replacing it. The 67 was blown down "every Sunday after Church". @Steamhead, looked through the Steam Bible previous and in the Library on this site. Diagrams and descriptions are close but not exact. Didn't check to see if the radiators had union elbows on them. ( page 257 ) but will next visit. @Both of useguys, I vaugly remember something that Dan wrote somewhere about a system like this with those darn Trane "throttle" valves and to be very careful with them. Does it ring a bell? Would love to more about them. All your help is much appreciated.

nicholas bonham-carter

Trance valves

Put a good low-pressure gauge (gauge store.com, 0-3 psi) on that system, and see if the pressure can be kept as low as possible(ounces?). Until there is a proper main vent on there, the combination of high pressure, and bad venting could force water up into the returns, each time triggering the auto/over-fill to activate.

Those valves are probably adjustable so that at maximum opening, they will only let in the small amount of steam which can be condensed. Summertime will be a good time to take the valve apart and restore it.

Why not turn off the auto/over-fill, and see if the waterline stabilizes, after fixing the leaky return.-NBC