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Hissing Return Vents

rhw
rhw Member Posts: 49
Wet return vents were hissing this morning for the first time. They were installed several years ago. Also it seems that the water level in the sight glass has gone down some although no obvious leaks and no white smoke coming out of the stack. Is this something that needs to be addressed immediately? I have attached some pictures and there are others from a previous post. All help greatly appreciated
Thanks.

Comments

  • neilc
    neilc Member Posts: 2,689
    What's your boiler pressure set to?
    What do you see on the gage at its highest?
    Post a picture of the boiler and the control and gage.
    known to beat dead horses
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    edited November 2018
    No doubt your pressure may have increased beyond the maximum set on the pressuretrol. This can be caused by the pigtail underneath becoming plugged. The cure is to remove the pressuretrol, and unscrew the pigtail, to give it a good wash out. Check the settings on the pressuretrol at this time as well, and set it as low as possible,-1.5 psi off, and 1 on.
    Getting a low pressure gauge, (1-3 psi) is so important for keeping these systems honest, that I don’t know why they are not supplied with each new boiler, along with the required 0-30 psi gauge.
    Unless your system is very very small, that main vent is too small to get the air out quickly. Perfect balance, with the steam arriving at each radiator simultaneously, needs the air to be let out with very low resistance.—NBC
  • rhw
    rhw Member Posts: 49

  • gennady
    gennady Member Posts: 839
    edited November 2018
    If air vent fails open, escaping steam makes hissing noise. Steam gets lost and water level drops, if you have no automatic feeder, which refills boiler to maintain water level. Replace hissing air vent.
  • neilc
    neilc Member Posts: 2,689
    Looks like you have room to dial the Ptrol down a bit and lower your pressure setting.
    Is that picture taken while the boiler is running?
    Is the pigtail clear.
    How does the water look in your sightglass? Dirty ?
    known to beat dead horses
  • rhw
    rhw Member Posts: 49
    yes. picture taken while boiler was running and have not removed pigtail to see if clear. also sight glass water does not look particularly dirty.
  • neilc
    neilc Member Posts: 2,689
    clean water is good,
    check that pigtail.
    known to beat dead horses
  • rhw
    rhw Member Posts: 49
    Will do. If I can figure out how to do. Is there a youtube or other video instruction guide somewhere? Thanks.
  • Jamie Hall
    Jamie Hall Member Posts: 23,159
    Ah... back up a moment. If this hissing vent is on a return (and not on an extension of the steam main), you may have a failed trap out there in the system somewhere. Check them all.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • rhw
    rhw Member Posts: 49
    I now think the hissing of the vents on the returns "may" have occurred due to a Thanksgiving guest who boosted the thermostat by 5 degrees to try and warm up the house fast since it has not happened since that time. However it appears that I am still adding water to the boiler once every two weeks. Not sure how much but the boiler shuts down and a red light goes on. Any thoughts on a fix?
  • Jamie Hall
    Jamie Hall Member Posts: 23,159
    Probably right. Nothing like folks tampering with thermostats.. (ask me about a church I care for someday).

    How much water are you adding? A gallon or so every two weeks isn't that bad. Be nice if it were less, but so long as it is consistent... and finding out where it's going could be a real bear. That small a loss just isn't going to show up real well.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • JUGHNE
    JUGHNE Member Posts: 11,042
    Jamie, churches and thermostats...I know off topic but:
    I put 2 Visonpro's in a church mainly because of the locking feature. The screen is locked on setting "1". They can raise or lower temp until the next time programed. I have to go there twice a year to change from heat to cool and back.
    The church leaders asked to a meeting to explain how to operate the T-stat. The deer in headlights were all gathered around the table.
    They said they wanted to know about it as I would not be around forever...….I was the youngest person in the room.
    ethicalpaulDan C.
  • BobC
    BobC Member Posts: 5,476
    @Jamie Hall I was working at a factory when the first energy crunch hit, the owner was outraged at the cost of heating the plant and wanted to lower costs

    He knew I had just installed a new setback thermometer and asked it could be done for the plant. I warned him about all the mass that would have to be brought up to temperature but he wanted it done. I requisitioned the thermostat and set the thing up but I mounted it on a partition so it was out of sight so the workers could diddle the now disconnected thermostat to their hearts delight.

    The boss initially wanted the heat to come back up at 7AM but that left the plant frigid when people started working at 8AM. I walked it back to 5AM which meant things had come most of the way back by the time folks clocked on.

    Bob
    Smith G8-3 with EZ Gas @ 90,000 BTU, Single pipe steam
    Vaporstat with a 12oz cut-out and 4oz cut-in
    3PSI gauge
  • rhw
    rhw Member Posts: 49
    Looks like water is below the LWCO and shutting down the boiler in a weeks time. Where is it going? Again I see no leaks or white smoke.
  • Fred
    Fred Member Posts: 8,542
    Do you have any returns buried under the basement floor? That much water has to be going somewhere. Does the basement or any other rooms in the house seem unusually humid? That may be a clue to a faulty vent. Is this a one pipe or two pipe system?
    Have you cleaned the pigtail yet and reduced the setting on the Pressuretrol?
  • Maybe it’s time to do the overfill test to discount a leak in the boiler itself.
    Turn the boiler off at the switch.
    Wait an hour or so to cool down to warm from hot.
    Fill with fresh water, until you can feel cold water in the header above the boiler.
    Wait a couple of hours or more, and check for water on the floor, or in the firebox.
    Don’t forget to drain down the boiler to the recommended level before turning it back on.
    Post the results here when you have completed this test.
    Is this system one pipe, or two?—NBC
    ethicalpaul
  • rhw
    rhw Member Posts: 49
    One pipe system and all piping is visible. No additional humidity in the house. Although I do a lot of diy stuff removing the pigtail for some reason seems a little daunting. Should it be? I will also knock the pressuretrol down a notch.

    As far as turning off the boiler I guess I should wait for a little warmer weather as I may get thrown out of the house. Right now our highs are in the upper 30's.

    Thanks for all your help but I'm still confused as to why I would lose all that water and not see a sign of it anywhere.
  • neilc
    neilc Member Posts: 2,689
    take the time and do NBC's test,
    that water might be going up the chimney.
    Send wife and kids to the movies.
    known to beat dead horses
    ethicalpaul
  • Fred
    Fred Member Posts: 8,542
    @rhw, taking the pigtail off and cleaning it is a simple task. Shouldn't take more than 15 minutes barring any surprises (which I know is what you are apprehensive about)
  • rhw
    rhw Member Posts: 49
    Took off the pigtail and cleaned it out. Getting it cleaned took much longer than expected. Probably did not have the right stuff to unclog it with. Fingers crossed that this is the fix. Thanks to everyone.
  • ethicalpaul
    ethicalpaul Member Posts: 5,694
    Was it clogged to the point of resisting air flow through it? If so, good work!
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • neilc
    neilc Member Posts: 2,689
    yeah, let us know either way if symptoms persist
    known to beat dead horses
  • rhw
    rhw Member Posts: 49
    It was so clogged that it resisted air flow. It took a while to clean out.
    ethicalpaul
  • rhw
    rhw Member Posts: 49
    Been out of commission for a while but seriously thinking of doing NBC's overfill test as now I am filling the boiler every 5 to 6 days (although due to the cold spell the boiler is running more).
    My boiler fills with hot water. Is this going to be a problem when filling to the header? Will I be able to feel the hotter water to know the refill has happened? Is this ok?
  • Fred
    Fred Member Posts: 8,542
    Yes, do the over fill test. Let the boiler cool and then you should be able to feel the warmer water in the pipe. If the boiler has a hole in it, you may not even have to fill it up into the risers. You may see water spilling onto the floor sooner than that.
  • rhw
    rhw Member Posts: 49
    Thanks Fred. Your advice is great and greatly appreciated! Still unsure as to why no smoke or steam coming out of chimney and no leaks in any pipes or radiators and no excessive steam coming from any vents. Yet still filling boiler every week give or take a day or two.
  • nicholas bonham-carter
    nicholas bonham-carter Member Posts: 8,576
    Is there a water softener on your hot water side?—NBC
    JUGHNE
  • rhw
    rhw Member Posts: 49
    nope
  • rhw
    rhw Member Posts: 49
    I am back again. Steam and some water spitting out of main vents. Did not do overfill test yet as no smoke coming out of chimney..if that matters? Water needs to be refilled almost every day now. Could the water loss be from these main vents as Gennady above suggested? Should I replace with bigmouths? Obviously trying to make it through this cold spell so as not to divert an expert from those totally without heat although I may be there soon. TIA.
  • No expert needed for the overfill test.—NBC
  • rhw
    rhw Member Posts: 49
    Thank you NBC. I understand. Fill with water and it leaks get a plumber. Fill with water and it does not leak but still losing water get a plumber.

    Trying to see if there is another cause that I can perhaps try. Thought that with the main vents shooting steam and spitting a bit of water that I needed something bigger or some other cause that I could fix. However If that does not work I have spent money that would have been better used by getting a plumber. Guess I will keep filling with water until I can get a plumber.
  • ethicalpaul
    ethicalpaul Member Posts: 5,694
    Did you lower your pressuretrol as recommended above? Have you seen the gauge move during a heating cycle since you cleaned your pigtail?
    NJ Steam Homeowner. See my sight glass boiler videos: https://bit.ly/3sZW1el
  • rhw
    rhw Member Posts: 49
    Gauge is 0-30 so it does not move. I guess I can get a different gauge. Lowered pressuretrol to just below 1 and dial inside to 1. Cleaned pigtail but not where it enters the boiler. Kind of at a loss. Any help, although I have already received lots, is greatly appreciated.
  • Fred
    Fred Member Posts: 8,542
    How much water do you estimate you are losing weekly? If a gallon or so, you have main or radiator vents or supply valves that are leaking. It's not always obvious. You can hold a mirror up to the vents and valves while the boiler is running and find those leaking steam. The mirror will fog up. A little water will be lost to evaporation, especially when radiator vents open immediately after a heating cycle.

    If you are losing several gallons a week, even though you may not see steam from the chimney, there is likely a hole in the boiler, above the water line. We are due for a warm spell, fill the boiler up, either into the risers on top of the boiler or until water spills on the floor, whichever comes first. If water comes out, Call a steam Pro, not a plumber. The boiler will need to be replaced. If you find leaky vents or valves, then it's ok to call a plumber but make sure he/she installs the correct vents and/or properly repacks the supply valve(s).
  • rhw
    rhw Member Posts: 49
    Thanks Fred. If the MAIN VENTS , Gorton 1's (2 years old on the returns) are shooting steam and spitting a bit of water for awhile during the heating cycle is this indicative of a problem and should they be cleaned or just replaced with something else?
  • I would use Gorton 2’s at a minimum, or a Big Mouth vent, if your pressure is always under 1.5 psi, (verified with a low pressure 0-3 psi) gauge.—NBC
  • Fred
    Fred Member Posts: 8,542
    @rhw By itself, it only indicates a bad vent. As Nick said, use a Gorton #2. They have the venting capacity of two Gorton #1's and can typically work fine for up to about 20 ft. of 2" main. My preference is the Barnes and Jones Big Mouth. Costs about the same as the Gorton #2, is solid brass and has about 2.5 times the venting capacity of the Gorton #2. Much more bang for the buck.
    ethicalpaul