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Secondary pressure backup for vaporstat

cdm
cdm Member Posts: 77
On my 3 year old boiler installation, I have had to replace 3 Honeywell Vaporstats. I want to add a pressure control unit in series with the Vaporstat to shut down the boiler (if) or when the vaporstst fails. Maybe at 2 psi. Suggestions for a unit or switch to use as a safety.

cdm


Comments

  • Jamie Hall
    Jamie Hall Member Posts: 17,095
    Why did your vepourstats fail? I'll grant you that they get kind of unhappy over around 7 to 10 psi or so, but they should have shut the boiler off long before then.

    Don't shoot the messenger. Find out why the vapourstats fail before you try to solve the problem.

    Now as to a second (or even third) pressuretrol, that's quite common. In fact, it's recommended practice -- and in some installations it's required. I'd suggest a secondary pressuretrol set at perhaps 2 psi cutout with a 1 psi differential. That becomes your safety, and the vapourstat becomes your control, which is what it should be.
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 10,317
    PA404A Honeywell or Residio or whatever they call themselves now
  • cdm
    cdm Member Posts: 77
    Thanks Jamie: I know Vaporstat should have shut down - but it didn’t ! Ed, thanks for the suggested pyrotrol 404-A, I’ll look into it.
  • neilc
    neilc Member Posts: 1,465
    is the pigtail clear ?
    is the pigtail present ?
    picture of trol and pigtail
  • cdm
    cdm Member Posts: 77
    Neil’s: yes, yes and not a (trol) but a Vaporstat. Thoroughly checked out system - micro switch on vapostat stuck. cdm

    switch is stuck
  • Jamie Hall
    Jamie Hall Member Posts: 17,095
    cdm said:

    Neil’s: yes, yes and not a (trol) but a Vaporstat. Thoroughly checked out system - micro switch on vapostat stuck. cdm

    switch is stuck

    badly overpressured. That will d oit. Or somebody pushed on it...
    Br. Jamie, osb
    Building superintendent/caretaker, 7200 sq. ft. historic house museum with dependencies in New England