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boiler gas pressure

Captain_Tom Member Posts: 1
We have a project with a 1974 CB model M60HP boiler (60 hp I guess), natural gas fired. The owner reports that the boiler has trouble firing if the gas pressure drops below 5 psi!!  I don't know any boiler that requires more than 7" of pressure, but this is an old piece of equipment, and may be different.

Can anyone shed some light on this? 


  • Tim McElwain
    Tim McElwain Member Posts: 4,481
    The supply pressure to the boiler

    is probably 5 pounds pressure and then reduced by regulation at the boiler. Do you have gauges for measuring pounds and also inches pressure?

    The conversion from HP to BTU's is 33,479 BTU/Hr times your 60 horsepower = 2,008,740 BTU's.
  • meplumber
    meplumber Member Posts: 678
    Timmy is dead on once again.

    That CB has a gas train on it that per CSD-1 has regulators on it with high and low gas pressure switches among other devices. The owners compliant would lead me to believe that the regulator to the main burner is malfunctioning. Is the pilot affected as well?

    There are of specific safety devices on large appliances. If you are not familiar with them, you could wind up another statistic. Seek some help if you are unsure.
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