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Raypak H3-0135B Low Heat

simonizer77 Member Posts: 3
Before I call my plumber yet again (when it rains it pours), I'm hoping you can help. I'm new to this taking over for my father who died last year leaving no knowledge behind. All temp gauges on boiler and in floor heating pumps are showing around 74 degrees. This is about half of normal. Is this anything I can fix, or should I call the professional. Runs on propane which is fine. Pilot light on and system is powered and running, just low heat temp. Thanks!


  • Tim McElwain
    Tim McElwain Member Posts: 4,494
    Is this the two

    stage version? You state that the pilot is on so I assume you are saying that the main burner is not on. Does the gas valve have a "red" handle (Robertshaw) if so make sure the handle is not on pilot it should be in the full on position.

    This boiler also has a boiler outlet sensor which could be holding the boiler off. There is a high limit, vent temperature switch, and flame roll out switch any one of those could be holding the system from running.

    Do you have a vent damper on this version?

    There is also a fast response temperature sensor which could also be holding the system off it shuts off the 24 volts to the ignition control.
  • simonizer77
    simonizer77 Member Posts: 3

    I believe it's a two stage, but know very little.  It's a complicated setup.  Pilot switch is at 'on' position.  Beyond that it's all greek to me.  Pilot is lit, but boiler never comes on.  I'll have to call plumber in the morning.  Getting aggravated as this will be the 4th call in 6 months.  I appreciate your efforts.