McQuay MCC 010C/CR, Manual, Page: 54 / 78

53
Model A B C D E F G H I J K
MCC030 C/CR
929.0 999.0 956.0 917.0 408.5 378.0 541.0 256.0 173.0 311.0 70.5
MCC040 C/CR
1045.0 1115.0 1072.0 1033.0 466.5 378.0 541.0 256.0 173.0 311.0 128.5
MCC050 C/CR
1299.0 1369.0 1326.0 1287.0 593.5 378.0 541.0 256.0 173.0 311.0 255.5
MCC060 C/CR
1499.0 1569.0 1526.0 1487.0 693.5 378.0 541.0 256.0 173.0 311.0 355.5
Pipings
Do not use contaminated or damaged copper tubings. If pipings, evaporator or condenser is exposed or had
been opened for 15 seconds or more, vacuum and purge with field supplied refrigerant. Generally, do not
remove plastic, rubber plugs or caps from fittings, tubings and coils unit ready to connect suction or liquid
line into fittings.
Piping connections are of flare type. If any brazing work is required, ensure that nitrogen gas is passed
through coil and joints while brazing work is being done. This will eliminate soot formation on the inside walls
of copper tubings.
Electrical Connection
As wiring regulations differ from each country, please refer to your LOCAL ELECTRICAL CODES for field
wiring regulations and ensure that they are complied with. Besides, take note of the following general
precaution
- Ensure that the rated voltage of the unit correspond to the name plate before commencing wiring work.
- Provide a power outlet to be used exclusively for each unit and a power supply disconnect and a circuit
breaker for over-current protection should be provided in the exclusive line.
- The unit must be EARTHED to prevent possible hazards due to insulation failure.
- All wiring must be firmly connected.
- Electrical wiring should not touch the refrigerant piping, compressor and any moving parts of the fan motor,
Operational Check
After all wiring is completed and system is charged with refrigerant, make sure unit is operating properly.
Check that: :
- Condenser fans are running with warm air blowing off the condenser coil.
- Evaporator fans are running and discharging cool air.
- Suction line pressures and condensing pressures are in the range of 60 - 75 psig. and 260 - 300 psig.
respectively in cooling cycle or 45 - 60 psig. and 245 - 285 psig. respectively in heating cycle.
- Microprocessor electronic thermostats as used in the remote controls incorporate a 3-minute delay in their
circuit. Thus it requires about 3-minute upon start-up before the outdoor unit is activated.