McQuay ACZ 045A, Инструкция по установке, эксплуатации и обслуживанию

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IOMM ACZ/AGZ-1 39
Extended
1. Front seat both condenser liquid line service valves.
2. Put both circuit switches in Pumpdown and Stop position.
3. After the compressors have stopped, put System Switch (S1) in Emergency Stop position.
4. Front seat both refrigerant circuit discharge valves.
5. If chilled water system is not drained, maintain power to the evaporator heater to prevent freezing.
Maintain heat tracing on the chilled water lines.
6. Drain evaporator and water piping to prevent freezing.
7. 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.
8. If electrical power is off, make provisions to power the evaporator heater (if chilled water system
is not drained). Tag all opened electrical disconnect switches to warm against startup 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 pre startup and startup 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 chiller into service.
Refrigerant Piping Checkout
1. Check all exposed brazed joints for evidence of leaks. Unit joints may 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 chiller.
3. Check all valve stem packing for leaks. Replace all refrigerant valve caps and tighten.
4. Check all refrigerant lines to insure that they will not vibrate against each other or against other
chiller components.
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.