Johnson Controls YEWS Series, Installation, Operation And Maintanance Instructions

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be power on when it is not running for a long period of
time (The compressor oil heat is also powered on).
If the main power has to be cutout in a long period of
service, the discharge service valve must be turn off, and
the oil heater has to run for more than 5 hours(24 hours
suggested) before the chiller starting.
If the chiller is required to close for a long time (such as a
whole winter), the following sections introduce the steps
need to be carried out:
1. It is required to inspect the sealing situation of the
system periodically in the period of long-term stop.
2. If the temperature in standby period is lower than the
water freezing temperature, it is required to drain out all
the water in the cooling tower, condenser, condenser
pump, chilled water system and chilled water pump.
Open the drain pipe in the evaporator and condenser to
ensure the complete drain.
Performing the periodical inspection and maintenance
according to the value displayed in the display panel, the
operator can avoid the serious operating default. The
following is the instructions of inspection content and
operation process.
7.5 Running detection
Performing the periodical detection and maintenance
according to the value displayed in the microcomputer
control center, the operator can avoid the serious running
default. The following detection content and method is a
good guide for user.
Daily
1. Inspect the displayed content of the display screen.
2. If the compressor is in running status, the bearing oil
pressure is required to be inspected.
3. Inspect the inlet and outlet water pressure and
temperature of the condenser so as to compare with those in
the design situation.
4. Inspect the leaving and entering temperature of the
chilled water and evaporator pressure o as to compare with
those in the design situation.
5. Inspect the condenser saturation temperature (confirmed
according to the condenser pressure detected by the
condenser sensor).
6. Inspect the discharge temperature of the compressor. The
discharge temperature should be lower than 75
℃
in usual.
7. Check that whether the condenser pipe is fouling or
blocking (the difference between the current condenser
approach temperature and the one measured in the new
chiller can not exceed 3
℃
)
8. Confirm whether the water has acceptable quality level.
9. Press Status key for displaying the alarming information
once there is a display requirement.
Weekly
Inspect the refrigerant charged record.
Quarterly
Performing the chemical analysis of the lubricant each 6
months (or perform the frequent inspection according to the
requirement)
Biannually
1. Inspect and replace the cartridge of compressor oil filter.
2. Oil return system
a. Clean the oil filter
b. Inspect the operational situation of ejector for finding the
impurity granule
3. Inspect the controller and safety protection device .
YEWS-E Water Cooling Screw Chiller/Heat Pump
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