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Radiator Valves

I had a question on main vents and radiator valves.

For main vents, why not just pick the largest capacity main vent? Is there a benefit of using a Gorton #1 rather than a Gorton #2?

For radiator valves, can I just use the largest valves (#C and D's) for all my radiators? Wouldn't quickly venting be the goal?


  • my theory too

    yes! put on the most capacious main venting you can buy, and install. you can never have too much.

    the larger vents will have a lower air velocity along with back-pressure, and will be less likely to plug up with debris over the course of a few years.--nbc
  • Rod
    Rod Posts: 2,067
    edited February 2011
    Radiator Venting

    Hi -  The following link has the best explanations that I've seen on here in a while on why mains are vented fast and radiators vented slowly. Be sure to also read Boiler Pro's link too.It's very informative!


       I think there are a lot of "retired " high capacity radiator vents bought back when that homeowner was new to steam, that are now sitting unused on the shelf.  I, myself, have some dusty old H.T. Vari-Vents  Large radiatior vents can be useful but only in isolated cases as a last resort.

    - Rod

    Edit Added-  Main Venting capacity wise - A Gorton #2 is equal to 3 + Gorton #1s and a Gorton #2 is equal to 2 Hoffman 75s.   Gortons and Hoffman seem to be the most popular main vents.
  • TeachMeSteam
    TeachMeSteam Member Posts: 128

    Thanks for the links. They were great. I understand now.

    So, I guess I'll use the Gorton #4 #5 or #6 from now on.

    Thanks again.
  • Steamhead
    Steamhead Member Posts: 15,521
    Another thing to look at when choosing main vents

    is how much air is in each main. If you size your main vents to vent this amount of airin about a minute at one or two ounces pressure, the steam will reach the end of each main at about the same time. This makes balancing the system much easier since every radiator take-off will have steam available at the same time when the main vents close. From that point, the radiator vents need only handle the air in the radiator run-out pipe and the radiator itself.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
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