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Which vaporstat

Luv'nsteam
Luv'nsteam Member Posts: 278
in Strictly Steam
In looking up a part number for the Honeywell vaporstat, L408J, I see there are two sub numbers.  One has a SPST switch (L408J1025) and the other has a SPDT (L408J1009).  I didn't notice any other differences (are there?). 



For my one-pipe vapor steam heating system, which one do I want?



Thank you,



Mike

Comments

  • Unknown
    Unknown
    L408J Vaporstats

    Hi Mike- Here's some info on Vaporstats for you.

    - Rod
  • Luv'nsteam
    Luv'nsteam Member Posts: 278
    Vaporstat choice

    Hi Rod, thanks for the PDF's.  After looking at them, I think I want the SPDT vaporstat.  I think this because the vaporstat, LWCO (float) and LWCO (probe) will be wired in series.  The L408J1009 has the SPDT switch and breaks contacts R/B on rise, where the SPST only makes on rise.  SInce I am using the vaportstat to shutdown the boiler on pressure rise, and only the 1009 vaporstat breaks on rise, this is the model I want, correct?



    Thank you,



    Mike
  • Steamhead
    Steamhead Member Posts: 16,832
    Yup

    you'd use the other one to shut off the burner if the pressure fell. The 1009 is the one you want.
    All Steamed Up, Inc.
    Towson, MD, USA
    Steam, Vapor & Hot-Water Heating Specialists
    Oil & Gas Burner Service
    Consulting
  • Luv'nsteam
    Luv'nsteam Member Posts: 278
    Much appreciated

    Steamhead and Rod, many thanks to both of you for your help.



    Have a great week,



    Mike
This discussion has been closed.

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