6 | Preparation
Installer reference guide
31
RZAG71~140N
Sky Air Alpha-series
4P695307-1A – 2024.02
Refrigerant piping diameter
The refrigerant piping diameters must comply with the following:
Piping Diameter
L1 (pair, twin, triple, double twin) See below.
L2,L3 (twin)
L2~L4 (triple)
L4~L7 (double twin)
Use the same diameters as the
connections (liquid, gas) on the indoor
units.
L2,L3 (double twin) Liquid piping: Ø9.5mm
Gas piping: Ø15.9mm
L1 (pair, twin, triple, double twin):
Model New
(a)
/
Existing
(b)
L1 liquid piping L1 gas piping
RZAG71 Size‑down Ø6.4mm Ø12.7mm
Standard Ø9.5mm Ø15.9mm
Size‑up Ø12.7mm —
RZAG100~140 Size‑down Ø6.4mm —
Standard Ø9.5mm Ø15.9mm
Size‑up Ø12.7mm Ø19.1mm
(a)
When installing new piping, use the same diameters as the connections on the outdoor
units (i.e. standard diameters for liquid and gas piping).
(b)
When reusing existing piping, you may use the size‑up or size‑down diameters, but then
capacity might decrease, and stricter piping length requirements are applicable. Assess
these limitations in relation to the complete installation.
Refrigerant piping length and height difference
The piping lengths and height differences must comply with the following requirements:
Requirement Limit
71 100 125+140
1 Minimum total one‑way piping
length
Pair: Limit≤L1
Twin: Limit≤L1+L3
Triple: Limit≤L1+L4
Double twin: Limit≤L1+L3+L7
3m
2 Maximum total one‑way piping
length
Pair: L1≤Limit Ø size-down 10m (10m)
(a)
Ø standard 55m
(75m)
(a)
85m (100m)
(a)
Ø size-up 25m
(35m)
(a)
35m (45m)
(a)
Twin and triple:
L1+L2≤Limit
Double twin:
L1+L2+L4≤Limit
Ø size-down 10m (15m)
(a)
Ø standard 55m
(75m)
(a)
85m (100m)
(a)
Ø size-up 25m
(35m)
(a)
35m (45m)
(a)