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Spraying vents

Customer has a 1 pipe system. The radiators at the ends both sprayed a rusty solution all over after I changed the vents on all the rads. I adjusted water level when I changed out the vents. Went back today to find the spray stains and extra water in the boiler. Manual feed no one has touched it since I was there last. Just looking for some things to investigate when I go back.
Aaron Hamilton Heating
[email protected]


  • neilcneilc Member Posts: 578
    show us where both those header pipes drop to,
    what's the pressure at?
    clean the pigtail,
    show us the main vent(s)
  • Aaron_in_MaineAaron_in_Maine Member Posts: 315
    Pigtail cleaned when I changed the rad vents. Set at the lowest setting on pressuretrol. No main vents just the vents on the rads. Someone tapped in the rad vent in the tee picture shown.
    Aaron Hamilton Heating
    [email protected]
  • Sometimes, setting the pressuretrol to the lowest pressure can disconnect the linkage inside, and allow it not to shut off on any pressure. Can you see any pressure on the gauge? A new 0-3 psi gauge would give you a better picture of what’s happening.
    Is the water clean, and the boiler piping as required by the manual?—NBC
  • the_donutthe_donut Member Posts: 374
    Did you adjust the water level shortly after a cycle while the boiler was still hot? Could be condensate lag causing issues or a mostly plugged return.
  • FredFred Member Posts: 7,261
    Make sure all rads are pitched back towards the supply pipe.
    Make sure all horizontal pipes (Mains, Radiator run-outs, returns) are pitched correctly
    Put some decent main vents on each main.
    Make sure water isn't leaking past the manual water supply valve.
    Double check that Pressuretrol is working properly. Setting it is one thing, its actual performance is another.
  • Steve_210Steve_210 Member Posts: 547
    Is there a automatic feeder if so is there a delay on the feeder.
    If not, Can you be sure the manual fill valve is shutting off 100 percent
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