CleaverBrooks FLX 1000, Operation, Service And Parts Manual

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General Description Chapter 3
750-177 3-9
13. Allow a small amount of fresh water to enter the boiler in order to create a slight overflow that will carry off surface
impurities. Continue to boil and overflow until the water clears.
14. It is difficult to provide specific recommendations regarding the duration of the cleaning process. In general, a period
of 18 to 36 hours will prove sufficient to internally clean the water-side of the boiler. The condition of the water blown
from the boiler is the best indicator as to whether the cleaning process is complete.
15. Discontinue firing, and allow the water to cool. After letting the water cool to 120°F or less, drain the boiler.
!
DANGER
WARNING
Be sure to drain the hot water to a safe point of discharge to avoid the possibility of scalding,
serious personal injury or death.
16. Remove the drum handhole cover, and wash the waterside surfaces thoroughly, using a high pressure water stream.
Direct the water stream into each individual tube. If possible, this washing should be done from the bottom up. A
wash out lance is available from your local Cleaver-Brooks authorized representative.
17. Inspect the waterside surfaces. If they are not clean, repeat the boilout procedures.
18. Replace the handhole covers (using new gaskets) and reinstall the relief valve(s).
19. If the boiler is to be put into service immediately, fill the boiler with clean, treated water and fire the burner until the
water has been heated to at least 180°F to drive off any dissolved gases that might otherwise corrode the metal.
20. If the boiler is not to be put into immediate service, refer to the section on boiler layup procedures in this chapter.
H. Washing Out
Depending on system integrity, feedwater quality, or operating conditions, the water side of the boiler may
need to be washed out on occasion.
In theory, a hot water system and boiler that have been initially cleaned, filled with clean, treated water, and
with no makeup water added, will require no further cleaning or treatment. However, minor system leaks may
allow the admission of additional water or air into the boiler.
Introduction of raw (untreated) makeup water or air to a hot water boiler may lead to pitting, corrosion, or
formation of sludge, sediment, or scale on the pressure vessel waterside.
The waterside condition of steam boilers can be likewise affected by feedwater quality, load demands,
operating conditions, or blowdown practices.
The waterside of a hot water or steam boiler should be cleaned and inspected no later than three months after
the boiler is put into service. Subsequent cleaning of waterside surfaces should be performed as indicated
through periodic inspection.
In order to thoroughly wash out the waterside of the pressure vessel, the handhole covers at the ends of the
upper and lower drums must be removed. The interior surfaces of the drums should be washed with a high
pressure hose. Tubes should be cleaned by directing a high pressure stream of water into the end of each tube,
first from the bottom, and then from the top drum.
Note: A washout lance for this purpose is available from your local Cleaver- Brooks authorized
representative.
Control and water column connections on steam boilers should be checked for accumulated deposits, and
cleaned as required.
After waterside cleaning has been completed, replace the handhole covers, using new gaskets.
Note: Handhole cover gaskets are installed dry; that is, without application of a sealing compound.