Johnson Controls YEWS Series, Инструкции по установке, эксплуатации и техническому обслуживанию

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The standard condenser tubes used in YORK YEWS-E
Chiller/Heat-Pump are internally enhanced copper tubes.
If the equipment is located in an unheated area
that is susceptible to freezing, the water must be
drained from the condenser to prevent tube
failure from freezing
.
Proper condenser water treatment can eliminate or
significantly reduce the formation of scale on the
waterside of the condenser tubes.
Maintain a minimum condenser water flow rate through
the tubes of at least 3.33 ft/sec. (1 meter/sec.). Through
tube water velocity should not exceed 12 ft/sec. (3.6
meter/sec.).
Condenser tubes must be maintained to provide proper
chiller operation. Condenser Approach Temperature is a
useful tool to monitor the performance of the condenser.
By recording and logging the Condenser Approach
Temperature as part of the chiller maintenance program,
this will provide a warning that the waterside condenser
tubes are fouled and require cleaning.Condenser
Approach Temperature is the difference between the
Condenser Leaving Water Temperature and the Saturated
Condensing Temperature.
If the approach increases above 5.0
℃
, or during the
annual condenser inspection and the tubes are observed to
be fouled, the tubes will require cleaning. For cond-enser
fluids other than water consult with the local YORK Field
Service Office for the correct condenser approach
temperature.
Condenser water side tube cleaning procedure
Two methods are used for waterside tube cleaning to
remove the scale; chemical and mechanical cleaning
procedures. The composition of the scale will determine
which method will be most effective to remove the scale
and dirt.
Consult with the local YORK Field Service Office for a
recommendation of the method(s) used in the local area.
Chemical Cleaning Procedure
Chemical cleaning is an effective method to remove scale
from internally enhanced copper tubes. However, a company
knowledgeable with the chemical cleaning procedure should
be contracted or consulted. Follow the chemical cleaning
company recommendations concerning solution cleaning
strength and time duration of the cleaning process.
Serious damage to thecondenser tubes will result if
the chemical cleaning procedure is improperly
applied.
Mechanical tube cleaning must always follow a
chemical cleaning procedure.
When chemical cleaning of the condenser tubes is required,
it may be necessary to calculate the internal volume of the
waterside condenser tubes. This information is necessary to
properly mix the correct concentration of cleaning solution.
Standard materials of construction for YORK YEWS-E
Chiller condensers is copper tubes and mild carbon steel
water boxes.
Mechanical Cleaning Procedure
1. Drain the water from the condenser.
2. Remove the water boxes from both ends of the condenser.
Use proper lifting equipment when removing the water
boxes. Use caution not to damage the threads on the
mounting studs that are welded to the tube sheet.
3. Select a tube cleaning brush for 3/4 inch I.D copper
condenser tubes. If tubes other than 3/4 inch copper are
used, select a tube cleaning brush that is made for the tube
size. Generally, brushes made of hard plastic or brass
bristled wires are preferred for cleaning copper tubes.
4. Attach the tube cleaning brush to the end of a cleaning
machine or cleaning rod.
5. Flush the condenser with clean water to remove the
debris.
CAUTION
WARNING
YEWS-E Water Cooling Screw Chiller/Heat Pump
WARNING
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