Daikin UCQ0060, Installation Operation & Maintenance

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7.0 COMMISIONING
PRE-STARTUP REQUIREMENTS
1. Inspect the unit for shipping or installation damage.
2. Verify the unit is completely and properly installed with ductwork connected. Verify that all construction debris is
removed and filters are clean.
3. With all electrical disconnects open, check all electrical connections to be sure they are tight.
4. Visually check for refrigerant piping leaks.
5. The compressor oil level should be maintained so that an oil level is visible in the sight glass. The oil level only
can be ascertained when the compressor is running in stabilized conditions, ensuring there is no liquid refrigerant in
the lower shell of the compressor. The oil level should be between ¼ and ¾ of the sight glass with compressor
running. At shutdown, the oil level can fall to the bottom limit of the oil sight glass.
7. Visually inspect field wiring (power and control). Wiring must meet local codes.
10. Check the tightness of setscrews in bearings, drives, and fan wheels
11. Verify the supply fan rotates freely. Verify proper drive alignment of the supply fan.
12. Verify the unit condenser water connections and condensate drain connections have been piped & closed for the
end which not been used.
13. Verify that all mechanical and electrical inspections have been completed per local codes.
14. Make sure the trap for the main evaporator drain pan has been primed by pouring water in the pan until water
exits the condensate drain line.
15. Connect wiring for water flow switch or remote switch by removing the jumper wire on the desired terminal
(refer wiring diagram on the unit).
15. Apply 3-phase power to the unit and verify that it falls within the specified voltage range.
16. Check for voltage imbalance. Voltage imbalance should not exceed 2% of the average voltage.
CRANKCASE HEATERS
The purpose of the crankcase heater is to prevent the migration of refrigerant to the crankcase during shutdown, to
assure proper lubrication on the compressor during start-up.
The heater is interlocked with the compressor contactor and is not controlled directly by the controller. When the
compressor is OFF, a normally closed auxiliary contact on the compressor contactor closes the circuit and energize
the crankcase heater.
CAUTION!
•
Do not bypass the high or low pressure switch during unit operation.
•
Do not bypass compressor and fan overload protector.
•
The crankcase heater must be turned on a minimum of 12 hours prior to start the compressor.
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The crankcase heater must be always energized when the unit is not running.