Single-Zone Piping Limitations; Multi-Zone Piping Limitations - Lennox MMA018SM4 Service Manual

8.6. Single-Zone Piping Limitations

INDOOR UNIT
Maximum
Elevation -
Outdooor
Unit BELOW
Indoor Unit
Do not allow for excess length of line sets to be left rolled up as part of the
required distance, or in general. This will also cause additional performance issues.
NOTE:
Note: Each system size has a line set length and vertical elevation parameters.
System Size (KBtu)
018
024/30
036/048/060

8.7. Multi-Zone Piping Limitations

CAUTION
In order to avoid injury, take proper precaution when lift-
ing heavy objects.
• The largest capacity indoor unit must be connected to the lowest refrigerant connection ports on the outdoor unit.
• The 24,000 Btu indoor unit is only allowed to be connected to MPC036S4M, MPC048S4M, MLB036S4M and
MLB048S4M outdoor units.
NOTE: Each indoor unit must be piped AND wired to the correct zone piping connections and wiring terminals. Make
sure that indoor unit A is wired to the zone A terminal block and connected to the appropriate refrigerant pipe
connections.
Connecting Multiple Capacity
Indoor Units
Four-Zone System Example
Shown Above
Maximum Line Set
Length
OUTDOOR UNIT
Minimum Line Set
Length - 10 ft. (3m)
Outside Unit BELOW Indoor Unit
Line Set Diameters
(in.)
Liquid Gas
1/4 1/2
3/8 5/8
3/8 5/8
Connecting Multiple Capacity Indoor Units
C(1/4in)
C(3/8in)
B(1/4in)
B(3/8in)
A(1/4in)
A(1/2in)
Maximum Line Set
Length
INDOOR UNIT
Outside Unit ABOVE Indoor Unit
IMPORTANT
Maximum Elevation
Outdoor Unit BELOW
Indoor Unit ft. (m)
66 ft. (20 m)
82 ft. (25 m)
98 ft. (30 m)
IMPORTANT
Pipe and wire to each zone separately.
Test each indoor unit separately to ensure proper opera-
tion.
52
Minimum Line Set
Length - 10 ft. (3m)
OUTDOOR UNIT
Maximum
Elevation -
Outdooor
Unit ABOVE
Indoor Unit
Maximum Elevation
Outdoor Unit ABOVE
Indoor Unit ft. (m)
66 ft. (20 m)
82 ft. (25 m)
98 ft. (30 m)
Pipe and Wire Each Zone
Separately
outdoor
wire
A B C D
pipe
L4(ft)
Unit D
L3(ft)
Unit C
L2(ft)
Unit B
L1(ft)
Unit A
Maximum Line Set
Length
ft. (m)
98 ft. (30 m)
164 ft. (50 m)
213 ft. (65 m)
indoor
Unit D
Unit C
Unit B
Unit A