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Balancing Radiators - Increase Venting on Cool Radiators or Decrease on Warm Radiators ?

Jeff_H Member Posts: 37
I have a one-pipe steam heating system and am trying to balance my radiators (my second floor is generally much warmer than my main floor). My instinct was to increase the venting on the radiators on the main floor (mostly VariValves), but I am wondering whether it might be better to decrease the venting on the second floor radiators (Maid-O-Midsts, which tend to make much more noise than the first floor radiators). Does anyone have any thoughts?



  • Abracadabra
    Abracadabra Member Posts: 1,948
    If your main venting is setup properly, it may take a combination of both (increase cool radiators and decrease warm radiators) I'd prefer to start with decreasing venting on radiators first. What size radiator vents are on there now?
  • Fred
    Fred Member Posts: 8,541
    The first thing you need to do is make sure you have enough venting on your Main(s). If you have two or more Mains, the venting needs to be adequate on each to allow steam to fill each of them at about the same time. That is the point that you can adjust your radiator vents to balance them. Trying to balance the radiators before the Mains simply won't be successful. How much venting and what type do you have on the Mains (near the end, after the last radiator run?
    Alsso make sure your Pressure is set correctly. The pressuretrol/Vaporstat should be set so that the Cut-in is about .5PSI ( if you have a Vaporstat @ about 4 OZ.) and the cut-out (differential at about 1PSI (About 12 OZ if you have a Vaporstat).
  • BobC
    BobC Member Posts: 5,412
    What pressure is the boiler operating at and are the mains adequately vented and balanced?

    Varivalves are very aggressive, why are you using those on your radiators? Even at low settings they are faster than most other vents.

    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • Jeff_H
    Jeff_H Member Posts: 37
    Thank you for your help. I have three Gorton 2s for main vents (two are in one place; one is separate - I'm not sure which is on the last run). Upstairs, I have Maid-O-Midst 5s on the larger radiators and either Maid-O-Midst 4s or VariValves (shut all the way) on the smaller radiators. On the main floor, I have VariValves (most are less than half open, other than two which are on radiators that take a very long time to warm up) and Vent-Rite #1s (one is about half open; one is almost totally open). My heating person recommended VariValves, but I began switching to Maid-O-Midsts and VentRites when the VariValves began spitting water. I chose Maid-O-Midsts for the upstairs bedroom because they are more quiet on those radiators than VentRite #1s, Gortons and Hoffmans (I have been having an issue with water gettting into them; it's possible radiators are not pitched correctly, which I plan to look into).
  • Abracadabra
    Abracadabra Member Posts: 1,948
    I like using the MOM when balancing since they have the replaceable orfices. Makes things a bit easier.
  • Jeff_H
    Jeff_H Member Posts: 37
    I was thinking the same thing about Maid-O-Midsts.

    Is there any downside to going to lower numbered vents on the radiators that are heating quickest? In other words, would I risk losing any steam to the other radiators or is the likely scenario that those other radiators will get more heat than they do now (or does it depend on which radiators get steam first - based on their location)?
  • Abracadabra
    Abracadabra Member Posts: 1,948
    Venting the radiators slow is best. Only increase the venting if you aren't getting heat to the end of the radiator as fast as you'd like.