McQuay MCM 020 D, Руководство пользователя

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(3) Refrigerant Piping
Maximum Pipe Length And Maximum Number Of Bends
•
When the pipe length becomes too long, both the capacity and reliability drop. As the number of bends
increases, system piping resistance to the refrigerant flow increases, thus lowering the cooling capacity,
and as the result the
font compressor may become defective. Always choose the shortest path and follow
the recommendation as tabulated below:
MODEL
DATA
020 025/ 030B 030C 035/ 040 050 060/ 061/ 062
Max. Length, L 15m 15m 35m 35m 35m 35m
Max. Elevation, H 8m 8m 15m 15m 15m 20m
Max. No. of bends 10 10 10 10 10 10
Piping Sizes (Flare Connection Type)
Piping sizes are as follows:
MODEL 020 025/ 030B 030C 035/ 040 050 060/ 061/ 062
Liquid (mm/in) 6.35(1/4) 9.52(3/8) 9.52(3/8) 9.52(3/8) 9.52(3/8) 12.7(1/2)
Suction (mm/in) 15.88(5/8) 15.88 (5/8) 15.88 (5/8) 19.05 (3/4) 19.05 (3/4) 19.05(3/4)
Piping Connection to the Units
•
Align the center of the piping and sufficiently tighten the flare nut with fingers.
•
Finally, tighten the flare nut with torque wrench until the wrench clicks.
•
When tightening the flare nut with torque wrench, ensure the direction for tightening follows the arrow on
the wrench.
PIPE SIZE (mm/in) TORQUE (Nm)
6.35(1/4) 18
9.53(3/8) 42
12.7(1/2) 55
15.88(5/8) 65
19.05(3/4) 78
(4) Wiring
Electrical Connections
•
Wiring regulations on wire diameters differ from country to country. Please refer to your LOCAL
ELECTRICAL CODES for field wiring rules. Be sure that installation comply with such rules and regulations.
General Precautions
•
Ensure that the rated voltage of the unit corresponds to the name plate before carrying out proper wiring
according to the wiring diagram.
•
Provide a power outlet to be used exclusively for each unit. A power supply disconnect and a circuit
breaker for over-current protection should be provided in the exclusive line.
•
The unit must be GROUNDED to prevent possible hazards due to insulation failures.
•
All wiring must be firmly connected.
•
All wiring must not touch the hot refrigerant piping, compressor or any moving parts of fan motors.
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