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Mascot ii boiler test

Hello everyone,

I have a new old stock (used for a demo kind of deal) mascot ii boiler that I have been working on installing. I have power hooked up and the primary loop made and filled with water and when I call for heat the valve inside the boiler will open but nothing else happens. Screen doesn’t show anything, pump doesn’t turn on. Exhaust fan doesn’t purge, nothing. The only thing I have not run and hooked up yet is the propane line. I don’t see anything in any schematics for a pressure switch for the gas. Is anyone familiar with these units and aware of any failsafe switches that would prevent a startup with no gas pressure? I would love to make sure the components work before I finish everything and find out afterwards something’s broken.
Thank you

Comments

  • Jolly Bodger
    Jolly Bodger Member Posts: 209
    Does the screen show anything? Seems like it should be active for programming even if there was a fault.
  • nickmg555
    nickmg555 Member Posts: 16
    Sorry, I should have been more clear. The screen displays the standard standby with what I believe is current outlet temp. When call for heat signal is sent the screen does not change at all the only thing that occurs is the 24v valve inside opens.

    Does the screen show anything? Seems like it should be active for programming even if there was a fault.

  • Jolly Bodger
    Jolly Bodger Member Posts: 209
    No call for primary circulator? And it does not show heating call on the screen or fault code? Sounds like an issue. Hope you get response from someone with experience with the model. I have not had my hands on one.

    My next step you be to test the safeties and check the programming. make sure it is not looking for another external interlock.
  • EBEBRATT-Ed
    EBEBRATT-Ed Member Posts: 15,452
    Your just going to have to take the wiring schematic and a test meter and find what component is not allowing the unit to start. could be a simple wiring issue
  • nickmg555
    nickmg555 Member Posts: 16
    UPDATE: boiler is fine. Brought the multimeter and followed the call for heat circuit and found that the zone controller was faulty and not always closing the circuit. Then I opened up the valve to the not yet installed secondary loop pump just enough to allow a steady stream just in case there was a flow sensor which the diagram only shows one in the DHW loop and just like that it came to life. Now if ups would push through this snow storm and get me my fancy new taco delta T variable circulator pump I could get this thing together and get the gas hooked up and start throwing some heat ;)