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HydroTherm MR series with -P and -PV suffix

Marques Member Posts: 1
Hello everyone,

I was hoping someone may have some insight as to what the -P/PV suffix may mean. I've been searching but to no avail as to what the difference is between a HydroTherm MR-900B, MR-900B-P and MR-900B-PV

Any help would be greatly appreciated.
Thank you!


  • Zman
    Zman Member Posts: 7,572
    Just a guess here. It probably designates the type of pilot and maybe whether it has a vent damper.
    I quick call to the rep would answer it for certain.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • Steve Thompson (Taco)
    P is Standing Pilot, PV is Spark Ignition with Vent Damper if memory serves me correct (I was a Hydrotherm rep in the late 70's - learned how to troubleshoot with Hydropulse :-).