START-UP
I.
CAUTION: Complete the required procedures given in the
Do not jumper any safety devices when operating the unit.
Do not operate the compressor when the outdoor tem- perature is below 25 F (24 C) (unless accessory low am- bient kit is installed).
A. Checking Cooling Control Operation
Start and check the unit for proper cooling control operation as follows:
1.Place room thermostat SYSTEM switch in OFF posi- tion. Observe that blower motor starts when FAN switch is placed in ON position and shuts down when FAN switch is placed in AUTO. position.
2.Place SYSTEM switch in COOL position and FAN switch in AUTO. position. Set cooling control below room tem- perature. Observe that compressor and condenser- and
B.Unit Controls
All units have the following
Compressor Overload
This overload interrupts power to the compressor when either the current or internal motor winding temperature be- come excessive, and automatically resets when the internal temperature drops to a safe level. This overload may require up to 60 minutes (or longer) to reset. If the internal overload is suspected of being open, disconnect the electrical power to the unit and check the circuit through the overload with an ohmmeter or continuity tester.
Time Guard II Device
The unit is equipped with accessory Time Guard II recycle timer. The device will cause a
When
Low-Pressure/Loss of Charge Switch (LPS)
When the liquid line pressure drops below 7 psig (48 kPa), the LPS opens
High-Pressure Switch (HPS)
When the refrigerant
C. Sequence of Operation
At
Terminals G and C) will also open, allowing the system to function in cooling. As cooling demand is satis®ed, the ther- mostat contacts break, deenergizing the contactor causing the system to shut off. The liquid line solenoid (LLS) valve closes, minimizing the potential for refrigerant migration at this time. The compressor does not restart until the thermostat again calls for cooling. If a demand for cooling occurs within 5 min- utes after the thermostat is satis®ed, the system will not re- start due to the feature of Time Guard II device. After the
The system is protected with a
The crankcase heaters must be energized for a minimum of 24 hours before starting a 569C and 576B unit.
D. Oil Charge
576B Units
Allow unit to run for about 20 minutes. Stop unit and check compressor oil level. Add oil only if necessary to bring oil into view in sight glass. Use only approved compressor oil.
Approved oils are:
Suniso 3GS
If oil is added, run unit for an additional 10 minutes. Stop unit and check oil level. If level is still low, add oil only after determining that piping system is designed for proper oil re- turn and that system is not leaking oil.
569C Units
The 569C units do not have a sight glass and are factory charged with the correct amount of oil.
All Units
Do not reuse drained oil or use any oil that has been exposed to the atmosphere. Procedures for adding or removing oil are given in the Standard Service Techniques Manual, Chapter 1, Refrigerants.
CARE AND MAINTENANCE
To ensure continuing high performance and to minimize the possibility of premature equipment failure, periodic mainte- nance must be performed on this equipment. This cooling unit should be inspected at least once each year by a quali®ed serv- ice person.
NOTE TO EQUIPMENT OWNER: Consult your local dealer about the availability of a maintenance contract.
WARNING: The ability to properly perform mainte- nance on this equipment requires certain expertise, mechanical skills, tools, and equipment. If you do not possess these, do not attempt to perform any mainte- nance on this equipment other than those procedures recommended in the User's Manual. FAILURE TO HEED THIS WARNING COULD RESULT IN SERIOUS PER- SONAL INJURY AND POSSIBLE DAMAGE TO THIS EQUIPMENT.
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