Grounding; Supply Voltage; Preparation - Power On; Switch Settings - York YCWL0056SE Installation Operation & Maintenance

Water-cooled liquid chillers
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SECTION 6 – COMMISSIONING

Grounding

Verify that the unit's protective ground terminal(s) are
properly connected to a suitable grounding point. En-
sure that all unit internal ground connections are tight.

Supply Voltage

Verify that the site voltage supply corresponds to the
unit requirement and is within the limits given in the
Technical Data Section.
PREPARATION – POWER ON
Perform the commissioning using the de-
tailed checks outlined in the "Equipment
Pre-startup and Startup Checklist" as the
commissioning procedure is carried out.
Apply power to the chiller. Turn ON the option panel
circuit breaker if supplied.
The machine is now live!

Switch Settings

Assure the chiller ON/OFF Unit Switch at the bottom
of the keypad is OFF. Place the optional circuit break-
er handle on the panel door to ON. The customer's dis-
connection devices can now be set to ON.
Verify the control panel display is illuminated.
the system switches under the SYSTEM SWITCHES
key are in the OFF position.

Compressor Heaters

Verify the compressor heaters are energized. If the
ambient temperature is above 96 °F (36 °C) the com-
pressor heaters must be on for at least 8 hours before
start-up to ensure all refrigerant liquid is driven out of
the compressor and the oil. If the ambient temperature
is below 86 °F (30 °C), allow 24 hours.
110

Water System

Verify the chilled liquid system has been installed cor-
rectly, and has been commissioned with the correct
direction of water flow through the cooler. The inlet
should be at the refrigerant piping connection end of
the cooler. Purge air from the top of the cooler using
the plugged air vent mounted on the top of the cooler
body.
Flow rates and pressure drops must be within the limits
given in the Technical Data Section. Operation outside
of these limits is undesirable and could cause damage.
If mains power must be switched OFF for extended
maintenance or an extended shutdown period, the com-
pressor suction, discharge and economizer service stop
valves should be closed (clockwise). If there is a pos-
sibility of liquid freezing due to low ambient tempera-
tures, the coolers should be drained or power should be
applied to the chiller. This will allow the cooler heater
to protect the cooler from freezing down to –20 °F. Be-
fore placing the unit back in service, valves should be
opened and power must be switched ON (if power is
removed for more than 8 hours) for at least 8 hours (24
hours if ambient temperature is below 86 °F [30 °C])
before the unit is restarted.

Flow Switch

Verify a chilled water flow switch is correctly fitted in
the customer's piping on the cooler outlet, and wired
into the control panel correctly using shielded cable.
There should be a straight run of at least 5 pipe diam-
eters on either side of the flow switch. The flow switch
Assure
should be connected to terminals 2 and 13 in the panel.

Temperature Sensor(s)

Ensure the leaving liquid temperature sensor is coated
with heat conductive compound (Part No. 013-00890-
000) and is inserted to the bottom of the water outlet
sensor well in the cooler. This sensor also provides
some freeze protection and must always be fully in-
serted in the water outlet sensor well.
FORM 201.26-NM1
ISSUE DATE: 1/19/2018
JOHNSON CONTROLS

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