Water Quality Control; Chemical Water Treatment; Replacement Of Water - York YHAU-CW Manual

SECTION 7 – MAINTENANCE

WATER QUALITY CONTROL

Use the following guidelines to be sure of the highest
water quality control standards:
• Limit the water pressure to the maximum safe
working pressure for chilled and cooling water.
• Install a 10-20 or finer mesh strainer in the chilled
and cooling water piping.
• Install a thermometer and a pressure gauge in the
inlet and the outlet of the chilled and cooling wa-
ter piping.
• Install tapping (with valve) for chemical cleaning
of the inlet and the outlet of the chilled and cool-
ing water piping.
• Install an air vent valve at the highest part of the
piping and a drain valve at the lowest part of the
piping.
• Replace the water regularly and control the water
quality. Operating the chiller for long periods of
time with low quality water will cause corrosion
and the production of scale.
• Make sure the shut off valves installed at the
chiller inlet of the chilled and cooling water are
completely open.
If the chiller runs without the valves com-
pletely open, a strong turbulent flow can
be generated. The turbulence may cause
damage in the water chamber case and
the copper tube of the chiller. If you need
to adjust the flow rate of the chilled and
cooling water, be sure to adjust the valves
installed at the outlet side of the chiller.
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CHEMICAL WATER TREATMENT

Since the mineral content of the water circulated
through the evaporator, condenser, absorber, and gen-
erator varies, the water used may corrode the tubes or
deposit heat resistant scale in them.
Perform a chemical analysis of the water before the
system is installed. Consult a reliable water treatment
company to determine if treatment is necessary. If it is,
the water treatment company can provide treatment for
the water to help prevent damage to the tubes.

REPLACEMENT OF WATER

Since the cooling water system can be polluted by vari-
ous factors, it must be cleaned and the water it in must
be replaced periodically. Generally, if the water is not
treated at all by the cooling tower, the recommended
interval to replace the cooling water is:
• District polluted with sulfurous acid gas --- 5 days
• Common district --- 10 days
If the water is blown manually or automatically, the
replacement period may be lengthened as follows.
• District polluted with sulfurous acid gas --- 1
month
• Common district --- 1 month
FORM 155.31-ICOM2.EN.UL
ISSUE DATE: 12/21/2018
JOHNSON CONTROLS