Gree MULTI18HP230V1CO Installation Manual page 17

TWD-1518 multi21+ install_printer.qxp_Layout 1 3/22/17 9:41 AM Page 33
PIPING INSTALLATION
Piping Connections to Outdoor Unit
3. Apply a small amount of refrigerant oil to the flare connection on the refrigerant pipe.
4. Properly align piping and tighten flare nut using a standard wrench and a torque
wrench as shown in the indoor piping section.
5. Carefully tighten flare nuts to correct torque level referring to the following Torque Table:
Pipe Diameter Nut Size
inch (mm) inch (mm)
1/4 (6.35)
3/8 (9.5)
1/2 (12.7)
5/8 (15.9)
NOTE: Over tightening may damage flare connections and cause leaks.
(con't)
Torque Table
Tightening Torque
ft-lbs N-m
1/4 (17) 10 to 13 14 to 18
3/8 (22) 25 to 30 34 to 42
1/2 (25) 36 to 45 49 to 61
5/8 (29) 50 to 60 68 to 82
INDOOR UNIT INSTALLATION
Piping Height Requirements
The system piping layout must take in the constraints of vertical height on system performance.
The outdoor unit has a vertical height limit in which it can properly circulate refrigerant in the system.
1
The maximum elevation (H1) from the bottom
of the outdoor unit to the bottom of the highest
mounted indoor units must be less than:
Capacity Size (BtuH) Distance ft (m)
18,000 33 (10)
24,000 33 (10)
30,000 49 (15)
36,000 49 (15)
42,000 49 (15)
Verify your H1 and H2 maximum elevation measurements are less than the system limits.
Oil Return Bend
When the outdoor unit is more than 30 feet above the
indoor unit, an oil return bend must be added for every
20 feet of connection pipe.
26
2
L2
L3
...Ln
The maximum elevation (H2) between those
two indoor units from bottom of one unit to
bottom of the other unit must be less than:
Capacity Size (BtuH) Distance ft (m)
18,000 33 (10)
24,000 33 (10)
30,000 33 (10)
36,000 33 (10)
42,000 33 (10)
Outdoor
Oil return bend
Indoor
Oil return bend
15