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Vent smorgasbord

I have tried a variety of vents on two radiators in bedrooms. Single pipe boiler.

Bedroom 1, occupant tends to complain too cold with various No. 4 (e.g., Maid-O-Mist, Gorton), or else too hot and also too noisy with Gorton "C". I spent some time listening to a Gorton C yesterday. The C appeared to be breathing in a few seconds, out a few seconds, just like a person breathes, with no discernible distinct shutoff or off period, it seems to transition directly from a breathing in to breathing out, and making a fair amount of noise while doing that. Every section was piping hot when I observed this. "So it's really hot, now, right?" This radiator is the farthest from the boiler. The "C" hole is much larger than a #4, so I am thinking of drilling-out a #4 to be something in-between. Personally, I was happiest with the Maid-O-Mist #4, because it was virtually silent and not spitting, but the occupant was not satisfied with rate of the sections heating up.

Bedroom 2 is on the same main but closer to the boiler. I don't have issues with the amount of heat, but on this one I am really stumped as to noise. On this radiator, I have tried Hoffman #40 (incessantly clicky-clacky practically 40 times a minute); Vent-Rite #11 (continuous hissing...does Vent-Rite ever shut OFF??); Gorton #4 (also seemingly too much hissing, is this one shutting off, also about half the Gorton or Maid-O-Mist types I throw on here seem to be a bit spitty). I put the same Hoffman 40 on a first floor radiator and it tended to be gratuitously clicky-clacky there, too, but maybe only 10 times a minute instead of 40 times a minute.

What am I doing wrong?

Most of the vents on the first floor are Gorton #4 vertical types, and they seem to be behaving mostly pretty well, quieter, they'll spit from time to time, but it's not a common thing. Most of these are on the other main.

I don't think I have wet steam problem. The level in the sight glass is stable, and the water use is pretty low. I realize I may need more main venting, but I am reluctant to try to remove old main vents in case they snap off while trying to unscrew them, and tapping additional new ones is somewhat beyond what I feel comfortable attempting.


  • KC_Jones
    KC_Jones Member Posts: 5,736
    On the first issue above, why did you jump from a #4 to a C? There is a #5 and #6 between those two. Drilling out a 4, if you got the hole size correct, could get it to be a 5 or 6, I just don't know what the actual hole size is.

    Some of the other issues you complain about are indicative of not enough main venting, too high pressure, or water laying due to a pipe sag or incorrect pitch. Any of those would require looking at other parts of the system, main venting, boiler piping, main piping etc. Some items we can help through pictures, but slope and pipe sag are an on site item only, can't diagnose through pictures. We could talk you through how to check.

    The clicking is due to the type of vent. Hoffman uses the alcohol filled capsule, the Gorton uses a spring of sorts. I prefer the Gorton's because of this, they are nice and quiet.
    2014 Weil Mclain EG-40
    EcoSteam ES-20 Advanced Boiler Control
    Boiler pictures updated 2/21/15
    EBEBRATT-Ed Member Posts: 15,512

    The vent breathing in and out is a classic sign of water laying in the bottom of a radiator or pipe. Something is not pitched the right way
  • neilc
    neilc Member Posts: 2,700
    after working out any sags, or wrong pitches,
    are the pipes insulated?
    known to beat dead horses
  • Hap_Hazzard
    Hap_Hazzard Member Posts: 2,846
    edited November 2021
    I would advise you not to drill out any of the vent ports, as this will lead to confusion later. Buy a new vent with the size you need and just swap the ports and keep the new vent as a spare. You'll need it sooner or later. The beauty of the Maid-o-Mist vents is the ability to change ports without changing vents. Also, when you need to replace a vent, you don't necessarily have to find one of the right size because you can use the port from the vent you're replacing. If you save the port every time you replace a bad vent, you'll end up with a collection of ports in all the available sizes that you can use on existing vents whenever you need to tinker with the balancing, so you can see how it can get confusing if any of them have been drilled out and don't match the indicated size anymore.
    Just another DIYer | King of Prussia, PA
    1983(?) Peerless G-561-W-S | 3" drop header, CG400-1090, VXT-24
  • Steamhead
    Steamhead Member Posts: 16,823
    Also, don't be afraid to upgrade your main vents. This will solve the problem of getting the last radiators hot.

    Where are you located?
    All Steamed Up, Inc.
    Towson, MD, USA
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