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2 Pipe Vapor System by Moat

I have a Moat vapor system which, thanks to Gerry Gill, is operating far more efficiently than it did when I bought the house. The house is a 2 story brick built in 1925 with R-46 in the attic with a radiant foil barrier. The boiler last time I checked was working at about half a pound of pressure. The problem is that my drafty 2nd floor gets much hotter than my draftier 1st floor. The 2nd floor has one room with a television, stereo, cable box etc which all give off a ton of heat so the room gets unpleasantly hot.

The original Moat valves are in place in all the rooms and although very hard to turn or sometimes won't turn at all appear to be o.k. I do not want to replace the valves since (if I understand correctly) vapor systems require special valves or I'd have to modify the new valves with a disc with a pin whole in it and I like the look of the original valves. So, I have removed and cleaned one of the valves (in the room that is way too hot) and do not see any apparent damage or failure. I intend to re-install the valve and move the calibration stops so that I can close the valve off completely (I hope).

Should I apply some kind of heat resistant lubrication to the valve parts? I was thinking of the grease used to lube the cam when re building an engine. (not that I've ever done that!)

Also I am concerned about the effect closing off more than one or two radiators would have the rest of the system. Will I end up building too much pressure or cause short cycle burner firing?

Any advice on these valves or a Moat Vapor System will be appreciated.

Thank You.
Tom Bauer, Detroit Mi


  • Tabauer
    Tabauer Member Posts: 3
    Fred, Thanks, I should have thought of that myself so I'm glad you were here to keep me out of trouble! I did find that there is a rubber? washer much like a faucet washer at the end of these valves which on some was gone completely and on others there were fragments of this washer broken away. Tomorrow I plan to look around for a suitable replacement. Meanwhile, I can now turn some of the valves and reduce the heat coming into some of the rooms that are getting too hot. I have to wonder though if dialing back radiators in some rooms isn't forcing more steam to others or creating too much steam pressure? System doesn't seem to short cycle.

    Abracadabra: It would not be too difficult to reduce draft on the lower floor...... just too expensive. I am replacing some windows this year and hope to do a few each year. Most of my first floor windows are stained or leaded glass and would require a restoration and a couple of them walked away when the house was vacant. I am chipping away at the windows and doors a little at a time. Chipping, Chipping, Chipping.... 8 years of chipping away....

    Thanks to both of you for the replies.
  • Tabauer
    Tabauer Member Posts: 3
    Thanks again, Fred. My next "mission" is going to be hunkering down on the drafty window repair & replacement.