CleaverBrooks CBLE, Operation And Maintenance Manual

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Inspection and Maintenance
8-18 750-91 (revised 2009)
Model CB-LE Packaged Boiler Manual
6.
Check occasionally that the fan is securely tightened to the motor shaft. Check the clearance between the fan
vanes and housing.
8.17 — Safety Valves
The safety valve is a very important safety device and deserves attention accordingly.
Follow the recommendations of your boiler inspector regarding valve inspection and testing. The frequency of test-
ing, either by the use of the lifting lever or by raising the steam pressure, should be based on the recommendation
of your boiler inspector and/or the valve manufacturer, and in accordance with sections VI and VII of the ASME
Boiler and Pressure Vessel Code.
Avoid excessive operation of the safety valve — even one opening can provide a means of leakage. Safety valves
should be operated only often enough to assure that they ar in good working order. When a pop test is required,
raise the operating pressure to the set pressure of the safety valve, allowing it to open and reseat as it would in nor-
mal service.
Do not hand operate the valve with less than 75% of the stamped set pressure exerted on the underside of the disc.
When hand operating, be sure to hold the valve in an open position long enough to purge accumulated foreign
material from the seat area and then allow the valve to snap shut.
Frequent usage of the safety valve will cause the seat and disc to become wire drawn or steam cut. This will cause
the valve to leak and necessitate downtime of the boiler for valve repair or replacement. Repair of a valve must be
done only by the manufacturer or his authorized representative.
Avoid having the operating pressure too near the safety valve set pressure. A 10% differential is recommended. An
even greater differential is desirable and will assure better seat tightness and valve longevity.
8.18 — Fuel Oil Metering Valve, Adjusting, and Relief Valves
In the event that a leak occurs in the packing of the metering valve, the packing nut should be snugged gradually to
stop the leak.
Do not over tighten the metering valve packing nut. Excessive tightening of the packing nut prevents free movement of
the metering stem. Failure to follow these instructions could result in equipment damage.
! Caution