The Plugged Safety Valve, the Lapsed Certificate, and the Wrong License

The answer is no, on three independent grounds, and any one of them is sufficient.

1. A boiler may not be fired with its safety valve removed and plugged. The plug eliminates the only device that protects the shell against overpressure. A 150 psig firetube boiler with 500 hp of input and no relief valve is one stuck contactor or failed pressure control away from a catastrophic failure. A threaded plug in a safety valve opening is a code violation, not a temporary expedient.
2. A boiler may not be operated with an expired inspection certificate. No. 2 must be inspected and certified before it carries pressure again. The lapse is the owner's problem to fix, not something to run through.
3. The relief operator's license class does not cover this equipment. A low-pressure license does not authorize charge of a 150 psig boiler. That means that even if No. 2 were sound, there would be no legally qualified operator on duty.

Direct the relief operator to keep No. 2 out of service, tag and lock the fuel supply if the site permits, and not to fire either boiler under his supervision. Then arrange coverage: return, or get a properly licensed high-pressure operator on site before anything runs. Temporary electric heat is a legitimate answer for the weekend.

Responsibility is layered, and the operator sits in the middle of it.

• The owner or user is responsible for compliance: current certificates, licensed operators, and safe equipment.
• The contractor created an unsafe condition and should not have done it; the plug must come out and the valve must be replaced with one of the correct capacity and set pressure, tested, sealed, and documented.
• The operator in responsible charge has a personal duty to refuse and to record the refusal. Your license follows you, not the building.

Document and report:

1. A written notice to the owner and manager stating that No. 2 is out of service, why, and what is required to return it to service. Verbal notice is not enough.
2. Log entries with dates, times, the valve removed, the plug installed, the names and license numbers of everyone involved, and the exact instruction you gave.
3. Notification to the enforcing authority and the insurance carrier that a safety valve was removed and plugged and that a certificate has lapsed. Do not assume the contractor or manager has reported it.
4. A refusal in writing if the manager presses the point, copied to the owner.

Do not sign or initial any log or work order describing the boiler as ready, and do not accept a verbal assurance that the valve "will be back Monday."

Return to service is a checklist with a paper trail, not a phone call.

• Remove the plug and install a safety valve of the correct capacity and set pressure for this boiler, properly stamped, sealed, and with no shutoff valve between the boiler and the valve. Verify the discharge piping is full size and routed to a safe location.
• Test the valve and confirm it is not leaking and lifts at its stamped pressure, and record the result.
• Complete the required inspection - internal and external as applicable - and obtain a current certificate before the boiler carries pressure. The lapse is not cured by the contractor's word.
• Verify the other safety devices were not disturbed during the work: low water fuel cutoffs, pressure controls and limit controls, flame safeguard, and the gauge glass and try cocks.
• Confirm a properly licensed high-pressure operator is on duty for the shift, and that the license is appropriate to 150 psig equipment.
• Record everything: the repair, the valve stamping and capacity, the inspector, the certificate number and date, and the operator on duty.

Until every line above is satisfied, No. 2 stays tagged out. A cold building is recoverable; a boiler failure is not.