Operating instructions

Shutdown
Temporary
1. Put both circuit switches to the OFF position (Pumpdown and Stop).
2. After compressors have stopped, put System Switch (S1) to OFF (emergency stop).
3. Turn off chilled water pump or air handler if applicable. Chilled water pump to operate while
compressors are pumping down.
To start the chiller after a temporary shutdown, follow the start-up instructions.
Extended
1. Front seat both condenser liquid line service valves.
2. Put both circuit switches to the OFF position (Pumpdown and Stop position.)
3. After the compressors have stopped, put System Switch (S1) to the OFF position (emergency
stop).
4. Front seat both refrigerant circuit discharge valves (if applicable).
5. If electrical power is on to unit, the compressor crankcase heaters will keep the liquid refrigerant
out of the compressor oil. This will minimize start-up time when putting the unit back into
service. The evaporator heater will be able to function.
6. If electrical power is off, tag all opened electrical disconnect switches to warn against start-up
before the refrigerant valves are in the correct operating position. When starting the unit,
electrical power must be on for 24 hours before starting the chiller.
To start the chiller after an extended shutdown, follow the prestart-up and start-up instructions.
Water Piping Checkout
1. Check the pump operation and vent all air from the system.
2. Circulate evaporator water checking for proper system pressure and pressure drop across the
chiller barrel. Compare the pressure drop to the evaporator water pressure drop curve.
3. Clean all water strainers before placing the unit into service.
Refrigerant Piping Checkout
1. Check all exposed brazed joints on the unit, as well as any field-installed piping, for evidence of
leaks. Joints can have been damaged during shipping or when the unit was installed.
2. Check that all refrigerant valves are either opened or closed as required for proper operation of
the unit.
3. A thorough leak test must be done using an approved electronic leak detector. Check all valve
stem packing for leaks. Replace all refrigerant valve caps and tighten.
4. Check all refrigerant lines to see that they will not vibrate against each other or against other unit
components and are properly supported.
5. Check all flare connections and all refrigerant threaded connectors.
6. Look for any signs of refrigerant leaks around the condenser coils and for damage during
shipping or installation.
7. Leak detector is applied externally to refrigerant joints at the factory. Do not confuse this residue
with an oil leak.
8. Connect refrigerant service gauges to each refrigerant circuit before starting unit.
60 ACZ / AGZ-BM IMM ACZ/AGZ-4