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Air Vents or Steam Whistles

JK_3 Member Posts: 240
It sounds like your problem might be more than just venting. It might be that you are condensing to much steam back to water to quickly or mabye a partally blocked return. just food for thought before you commit your self to any one school of thought. by the way the only way to vent is with properly sized Gorton or Hoffman.

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  • Big Al
    Big Al Member Posts: 35

    I am new to steam heat, but I'm reading and learning a lot.

    When I moved into my house, all of the radiator vents were bad. They either never opened or never closed. I replaced everything with Watts SVA adjustable vents because that's what I could get easily. They all work, but they are quite noisy. They hiss loudly when they vent and really make a LOUD plink when they close. (Steam pressure .5 to 1.5 PSI) When the boiler cools off and draws air back in, some of the vents whistle like tea kettles.

    I found that If I close the adjusting cap pretty far, they are quieter. If I take the cap off entirely, there are two holes for air to go through . . . and they have a less piercing hiss and don't whistle.

    Is this typical of these vents? They look like they have a pretty big orifice. Are they unusually fast vents to begin with? Should I just replace them with something quieter? A local supplier got me a Legend (Dole clone) vent. It is quiet, but a lot slower.

    Any suggestions or others' experiences would be appreciated.
  • g rad
    g rad Member Posts: 7

    try switching to a dole 1933 vent,cost about $15.buy one only and put on offending rad.
  • Big Al
    Big Al Member Posts: 35

    OK, the Dole and the Watts are both based on an alcohol filled bellows, as are the Hoffman and Legend. There are other vents like the Gorton or Jacobus based on a bimaetal strip. Can anybody tell me the basic advantages or disadvantages to the two basic designs . . . i.e. noise, reliability, longevity, etc.?
  • Well,

    that`s a matter of personal preference, and how deep your pockets are, but Gorton is praised highly here.
    Wish I could find a Canadian supplier.

  • scrook_2
    scrook_2 Member Posts: 610
    main vents?

    How are the vents on the end of the mains, in the cellar?
  • Big Al
    Big Al Member Posts: 35

    Main vent was recently replaced with a Hoffman Specialties No. 75. There was no real change in the whistling. It doesn't happen every time the boiler shuts down either. The sequence that the vents re-open seems to be somewhat random. If a wide-open one opens first, it really whistles until more open up and share the load.
  • Big Al
    Big Al Member Posts: 35

    The main loop in the basement is 70 feet of 2 1/2" pipe, asbestos insulated, dry return. The main vent is right near the end. The radiators that sometimes whistle are pretty big . . . 6 tube, about 2 feet high and four feet long.
  • Chris Jones_3
    Chris Jones_3 Member Posts: 12

    I have Dole adjustable vents from the 1960's that are quite noisy also. They all seem to be working properly and the main vents were replaced last year with Gorton #2 vents based on help fron the Wall. They radiator vents were boiled out in vinegar last year which improved their operation. I believe that the noise may be the nature of the beast with this type vent.
  • Steamhead (in transit)
    Steamhead (in transit) Member Posts: 6,688
    That #75 is too small

    you need two Gorton #2 vents to properly vent that main.

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  • Big Al
    Big Al Member Posts: 35

    Thanks, Steamhead.

    I think you are right about the 75 being small. Before I got your reply I went out and bought a Heat-Timer Varivalve for the last radiator on the loop . . . one that was slow to heat up anyway. I know that those vents are not highly regarded here, but it did the trick. Since it's on the last radiator, it helps vent the entire main, and it's quiet . . . a gentle whoosh, a momentary sizzle, and then silent. It took a good five minutes off the warm-up time, gave me a nice warm room . . . and no more whistling anywhere at shut down. If it gives me too much grief, I'll replace it with something else and add a second #75 to the main. In order to get those big Gorton #2 vents to fit under the floor, I'd have to re-pipe the vent and that means disturbing the asbestos insulation. Abatement isn't in this year's budget.

    The rest of the vents are still noisy when they heat up and close . . . ssssssss PING! but at least they aren't in my bedroom.
  • Big Al
    Big Al Member Posts: 35

    Last night the Varivalve was making a strange soft burbling noise for a couple of minutes. (I've heard babies make a similar noise.) I turned on the light and watched. It didn't spit out any actual water . . . but it was blowing bubbles. Very, very strange . . .
  • Larry C_14
    Larry C_14 Member Posts: 4
    Vent blowing bubbles.

    Phosphates and oil makes soap.

    How clean is the sight glass on the boiler?

    How steady is the water level in the sight glass?

    Larry C
  • Big Al
    Big Al Member Posts: 35

    I don't think water quality/cleanliness is an issue.

    Sight glass is clean and clear, dry above the water line.

    At full boil, the water in the sight glass bounces maybe 1/2 inch.

    The vent stopped blowing bubbles, and the other vents are OK. It was only a couple of days old when it happened. Maybe there was some manufacturing debris left in the Varivalve that made the bubbles. It seems to open and close more gradually than the other vents in the system. (It doesn't snap open and shut.) It's also configured much differently . . . with the bellows above the vent opening and the vent opening barely above the connection to the radiator. It would seem that any condensate that finds its way into the Varivalve would more easily get blown out.

    I do like the fact that the vent is really quiet and fast. When it's venting full bore, it sounds more like a coffee maker than a tea kettle. Our bedroom is nice and cozy warm and the vent doesn't wake me up anymore.
This discussion has been closed.