5 Piping installation
Installation manual
8
4MWXM-A9
R32 Split series
3P600450-7T – 2022.09
a 100mm above expected level of snow
4.2.2 To install the outdoor unit
4.2.3 To provide drainage
NOTICE
In cold areas, do NOT use a drain socket, hose and caps
(large, small) with the outdoor unit. Take adequate
measures so that the evacuated condensate CANNOT
freeze.
NOTICE
If the drain holes of the outdoor unit are blocked up by a
mounting base or floor surface, place additional foot bases
≤30mm under the outdoor unit's feet.
▪ Use a drain socket for drainage if necessary.
a Drain hole
To close the drain holes and attach the drain
socket
1 Install drain caps (accessory f) and (accessory g). Make sure
the edges of the drain caps close off the holes completely.
2 Install the drain socket.
a Drain hole. Install a drain cap (large).
b Drain hole. Install a drain cap (small).
c Drain hole for drain socket
5 Piping installation
5.1 Preparing refrigerant piping
5.1.1 Refrigerant piping requirements
CAUTION
Piping and joints of a split system shall be made with
permanent joints when inside an occupied space except
joints directly connecting the piping to the indoor units.
NOTICE
The piping and other pressure-containing parts shall be
suitable for refrigerant. Use phosphoric acid deoxidised
seamless copper for refrigerant piping.
▪ Foreign materials inside pipes (including oils for fabrication) must
be ≤30mg/10m.
Refrigerant piping diameter
Liquid piping Gas piping
4× Ø6.4mm (1/4") 2× Ø9.5mm (3/8")
2× Ø12.7mm (1/2")
INFORMATION
Usage of reducers might be required based on the indoor
unit. See "5.2.1Connections between outdoor and indoor
unit using reducers"[49] for more information.
Refrigerant piping material
▪ Piping material: phosphoric acid deoxidised seamless copper
▪ Flare connections: Only use annealed material.
▪ Piping temper grade and thickness:
Outer diameter
(Ø)
Temper grade Thickness (t)
(a)
6.4mm (1/4") Annealed (O) ≥0.8mm
9.5mm (3/8")
12.7mm (1/2")
(a)
Depending on the applicable legislation and the maximum
working pressure of the unit (see "PS High" on the unit name
plate), larger piping thickness might be required.