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Step 3 - Check Condenser
There are three possible types of condensers present
in the chiller: Integral air-cooled, water-cooled, or
remote air-cooled. It is important to verify the chiller
will have adequate condenser cooling for proper
chiller operation.
Integral Air-Cooled Condenser Check
Make sure the chiller installation is as described in
the mechanical installation section of this manual.
Check to make sure the chiller condenser is clear of
obstructions and has at least 36 inches of open air
on the air inlet and outlets for proper airflow.
Water-Cooled Condenser Check
Check the condenser water lines to make sure all
connections are secure. Make sure sufficient
condenser water flow and pressure are available and
all shut-off valves are open.
Remote Air-Cooled Condenser Check
Check the refrigerant lines to make sure all
connections are secure and that a proper evacuation
of the chiller, the field piping, and the remote
condenser has occurred. Verify the refrigeration
piping installation is as described in the installation
section of this manual. Check the remote condenser
main power and control wiring to ensure all
connections are secure.
Step 4 – Check Refrigerant Valves
It is possible valves were closed during shipment or
installation. Verify that all refrigerant valves are open.
CAUTION: Do not operate the unit with the
compressor, oil line, or liquid line service valves
“CLOSED.” Failure to have these “OPEN” may cause
serious compressor damage.
Step 5 – Verify Freezestat Setting
Make sure the Freezestat setting is appropriate for
the operating conditions of the chiller. It should be
set at 10°F below the minimum chilled water
temperature setting that the chiller will be operating.
Reference Table 12 to be sure the coolant solution
has sufficient freeze protection (glycol) to handle at
least 5°F below the Freezestat setting. All chillers
ship from the factory with the Freezestat set at 38°F
to protect against a possible freeze-up if no glycol is
in the coolant. Once the proper glycol solution is
present, adjust the Freezestat to the appropriate
setting.
CAUTION: The manufacturer’s warranty does not
cover the evaporator from freezing. It is vital that the
Freezestat is set properly.
Step 6 – Turn On Control Power
Some chillers may have a control power switch. If
present, turn the control power switch on. If not
present, turning the main power on should turn the
control power on. When the control power is on, the
panel displays are illuminated. Due to extreme
ambient temperatures that may occur during
shipment, the High Refrigerant Pressure switch may
have tripped. If this is the case, disconnect the main
power and reset the High Refrigerant Pressure by
depressing the manual reset button located on the
switch. Reconnect the main power, turn the control
power on, and clear the alarm condition by pressing
the Alarm Reset button.
Step 7 – Establish Coolant Flow
Standard units have an internal pump. To energize
the pump press the Start button. If the unit does not
have an internal pump, energize the external pump
to establish flow through the chiller.
Note: The compressor will not start as long as the flow switch is
open. A positive flow through the evaporator is required before the
compressor can operate.
Set water flow using a discharge throttling valve or
flow control valve (by others). The valve should be
the same size as the To Process connection of the
chiller. Standard chillers require approximately 2.4
gpm/ton of nominal capacity. A significant increase
in flow beyond this in a standard chiller may result in
excessive pressure loss, which can negatively affect
chiller efficiency and in extreme cases may cause
premature wear or damage of internal components.
Step 8 – Intial Unit Operation
Enter the desired leaving fluid temperature on the
control panel. Unless otherwise specified, the chiller
is factory set to deliver coolant at 50°F. Adjust to the
desired operating temperature. The chiller should
now be controlling to the selected temperature.
Please note that if there is insufficient load the
compressor may cycle on and off causing swings in
temperature.
