750-96 (revised 2010)
Model CB Packaged Boiler Manual
2-7
2.5 — Cleaning
ditions are detected, the water consultant of feedwater treating company should be consulted for advice on
corrective action.
It is recommended that a properly sized water meter be installed in the raw water makeup line to accurately deter-
mine the amount of raw water admitted to the boiler (steam or hot water) to aid the water treatment program in
maintaining proper waterside conditions.
The general feeling exists that a hot water boiler does not require water treatment, but this is a false assumption.
The recommendation of a reliable water treating company or a water consultant should be followed rigidly. Even
though these units generally operate on closed systems and blowdown is seldom practiced, the need remains to
be alert to system water losses and a water meter is recommended for water makeup lines.
2.5 — Cleaning
2.5.1 — Hot Water and Steam Piping
Steam and water piping systems connected to the boiler may contain oil, grease, or foreign matter. These impuri-
ties must be removed to prevent damage to pressure vessel heating surfaces. On a steam system, the conden-
sate should be wasted until tests show the elimination of undesirable impurities. During the period that condensate
is wasted, attention must be given to the treatment of the raw water used as makeup so that an accumulation of
unwanted materials or corrosion does not occur. Follow the advice of your water treatment company.
On a hot water system, chemical cleaning is generally necessary and the entire system should be drained after
treatment. Consult water treatment companies for recommendation, cleaning compounds, and application proce-
dures.
2.5.2 — Pressure Vessel
The waterside of the pressure vessel must be kept clean from grease, sludge, and foreign material. Such depos-
its, if present, will not only shorten the life of the pressure vessel and interfere with efficient operation and function-
ing of control or safety devices, but might quite possibly cause unnecessary and expensive re-work, repairs, and
downtime.
The installation and operating conditions which the boiler will be subjected to should be considered and cleaning of
the waterside of the pressure vessel should be provided during the course of initial startup.
The pressure vessel and the steam and return lines or hot water piping represent, in effect, a closed system.
Although the steam and return (condensate) lines or the hot water piping system may have been previously
cleaned, it is possible that:
• Cleaning has been inadequate.
• Partial or total old system is involved.
• Conditions may prevent adequate cleaning of piping.
The pressure vessel waterside should be inspected on a periodic basis. This will reveal true internal conditions and
serve as a check against conditions indicated by chemical analysis of the boiler water. Inspection should be made
three months after initial starting and at regular 6-, 9-, or 12-month intervals thereafter. The frequency of further
periodic inspections will depend upon the internal conditions found.
To Next Page
Loading...
