CleaverBrooks FLX 1000, Руководство по эксплуатации, обслуживанию и запасным частям

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Inspection and Maintenance Chapter 7
750-177 7-5
• Do not paint, oil or otherwise cover any interior or working parts of the valve. A relief valve does not require any lubrication or
protective coating to work properly.
• Discharge piping must be properly arranged and supported so that its weight does not bear on the relief valve.
• Handle with care a valve that has been removed from the boiler. A dropped valve should be considered as damaged until it has
been inspected and passed by the valve manufacturer's authorized representative.
! DANGER
WARNING
Only properly certified personnel such as the relief valve manufacturer's representative should adjust or repair
the boiler relief valves. Failure to heed this warning could result in serious personal injury or death.
Relief valves should be operated only often enough to assure that they are in good working order. Follow the
recommendations of your boiler inspector regarding valve inspection and testing. The frequency and method
of testing should be based on the recommendation of your boiler inspector and/or the valve manufacturer, and
should be in accordance with Section IV of the ASME Boiler and Pressure Vessel Code.
Low Water Controls (Hot Water)
Most instances of major boiler damage result from operating with low water. Since low water cutoff devices
are set by the original manufacturer, no attempt should be made to adjust these controls in order to alter the
point of low water cutoff. If a low water cutoff should become erratic in operation, immediately replace it or
contact your local Cleaver-Brooks authorized representative for assistance.
It is essential to verify proper operation of low water cutoff devices as frequently as possible. However, it is
impractical to perform daily and monthly maintenance on some models of the low water cutoff devices on a
hot water boiler. Hot water systems are fully closed. Daily or monthly maintenance on some models of the low
water cutoff devices would involve draining the entire water content of the system and would require makeup
and additional feedwater treatment that might not otherwise be necessary.
To verify the proper operation of float style low water cutoff devices, the system must be drained. Remove the
operating mechanism from the bowl and check and clean the float ball, internal moving parts, and the bowl
housing. Also, check the cross-connecting piping to make certain that it is clean and free of obstruction.
It is impractical to blowdown the low water cutoff devices on a hot water boiler, since the entire water content
of the system would become involved. Many hot water systems are fully closed and any loss of water will
require makeup and additional feedwater treatment that might not otherwise be necessary. Since the boiler
and system arrangement usually make it impractical to perform daily and monthly maintenance of the low
water cutoff devices, it is essential to remove the operating mechanism from the bowl annually or more
frequently, if possible, to check and clean float bowl, internal moving parts, and the bowl housing. Also check
the cross- connecting piping to make certain that it is clean and free of obstruction.
! DANGER
WARNING
Safe operation of your boiler demands periodic inspection and maintenance of all low water cutoff devices. If
controls do not shut off the burner when the water level drops below the safe operating level, or if controls
appear in poor physical condition, or become erratic in operation, they must be repaired or replaced at once.
Failure to heed this warning could result in serious personal injury or death.
If test-n-check valves are installed on the float style low water cutoff devices, these controls can be tested by
opening the blow down valve. The test-n-check valves restrict water flow when the blow down valve is open
allowing water to drain from the control. The test-n-check valves permit testing of the control without draining
the entire system therefore allowing regularly scheduled verification of float style low water cutoff.
Low Water Controls (Steam Boilers)
The need to periodically check water level controls and the waterside of the pressure vessel cannot be
overemphasized. Most instances of major boiler damage are the result of operating with low water or the use
of untreated (or incorrectly treated) water.