Refrigerant Piping Insulation; Refrigerant Piping Length And Height Difference; Connecting The Refrigerant Piping; Connections Between Outdoor And Indoor Unit Using Reducers - Daikin 3MXM40A2V1B Installation Manual

5MXM90
Gas piping
INFORMATION
Usage of reducers might be required based on the indoor
unit. See "5.2.1 Connections between outdoor and indoor
reducers" [ 4 11] for more information.
unit using
Refrigerant piping material
▪ Piping material: Phosphoric acid deoxidised seamless copper.
▪ Flare connections: Only use annealed material.
▪ Piping temper grade and thickness:
Outer diameter Temper grade
(Ø)
6.4 mm (1/4") Annealed (O)
9.5 mm (3/8")
12.7 mm (1/2")
15.9 mm (5/8")
(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.
5.1.2

Refrigerant piping insulation

▪ Use polyethylene foam as insulation material:
▪ with a heat transfer rate between 0.041 and 0.052 W/mK (0.035
and 0.045 kcal/mh°C)
▪ with a heat resistance of at least 120°C
▪ Insulation thickness
Pipe outer diameter Insulation inner
(Ø ) diameter (Ø
p
6.4 mm (1/4") 8~10 mm
9.5 mm (3/8") 10~14 mm
12.7 mm (1/2") 14~16 mm
15.9 mm (5/8") 16~20 mm
Ø Ø
i i
Ø Ø
p p
t
If the temperature is higher than 30°C and the humidity is higher
than RH 80%, the thickness of the insulation materials should be at
least 20 mm to prevent condensation on the surface of the
insulation.
Use separate thermal insulation pipes for the gas and liquid
refrigerant piping.
5.1.3 Refrigerant piping length and height
difference
INFORMATION
For the Hybrid for Multi application and the DHW generator
for Multi, see the indoor unit installation manual for the
maximum allowable refrigerant piping length and height
difference.
The shorter the refrigerant piping, the better the performance of the
system.
The piping length and height differences must comply with the
following requirements.
2MXM-A, 3MXM-A, 4MXM-A, 5MXM-A
R32 Split series
3P600450-6M – 2021.12
2× Ø9.5 mm (3/8")
1× Ø12.7 mm (1/2")
2× Ø15.9 mm (5/8")
(a)
Thickness (t)
Ø
≥0.8 mm
t
≥1 mm
Insulation thickness
) (t)
i
≥10 mm
≥13 mm
≥13 mm
≥13 mm
Shortest allowable length per room is 3 m.
Outdoor unit Refrigerant piping
length to each indoor
unit
2MXM68, ≤25 m
3MXM40,
3MXM52,
3MXM68
4MXM68
4MXM80
5MXM90
INFORMATION
In case of combination of the outdoor unit 3MXM40 or
3MXM52 with the indoor units CVXM-A and/or FVXM-A,
the total liquid refrigerant piping length MUST be ≤30 m.
Height difference
outdoor-indoor
Outdoor unit installed ≤15 m
higher than indoor
unit
Outdoor unit installed ≤7.5 m
lower than at least 1
indoor unit
5.2

Connecting the refrigerant piping

DANGER: RISK OF BURNING/SCALDING
CAUTION
▪ No brazing or welding on site for units with R32
refrigerant charge during shipment.
▪ During installation of the refrigeration system, joining of
parts with at least one part charged shall be performed
taking into account the following requirements: inside
occupied spaces non-permanent joints are NOT
allowed for R32 refrigerant except for site made joints
directly connecting the indoor unit to piping. Site made
joints directly connecting piping to indoor units shall be
of non-permanent type.
CAUTION
Do NOT connect the embedded branch piping and the
outdoor unit when only carrying out piping work without
connecting the indoor unit in order to add another indoor
unit later.
5.2.1 Connections between outdoor and indoor
unit using reducers
INFORMATION
▪ For the DHW generator for Multi use the same reducer
as for the 20 class indoor unit.
▪ For the Hybrid for Multi, see the indoor unit installation
manual for the capacity class and applicable reducer.
Total indoor unit capacity class that can be connected to this
outdoor unit:
Outdoor unit
2MXM68
3MXM40
3MXM52
3MXM68, 4MXM68
5 Piping installation
Refrigerant piping
total length
≤50 m
≤60 m
≤70 m
≤75 m
Height difference
indoor-indoor
≤7.5 m
≤15 m
Total indoor unit capacity
class
≤10.2 kW
≤7.0 kW
≤9.0 kW
≤11.0 kW
Installation manual
11