Mitsubishi Electric PUHY-RP200 Service Handbook page 57

[ II Restrictions ]
RP400, RP450, RP500, RP550 models
Outdoor unit
Outdoor unit
E
F
First liquid refrigerant distributor
A
First gas refrigerant distributor
First branch
(Branch joint)
Branch joint
Indoor
unit side
Piping
length
Outdoor
unit side
Height
difference
1) Maximum allowable piping length depends on the total amount of refrigerant in a given system. Use the formulas below to
calculate the maximum length.
PUHY-RP400 - RP550YSJM: 0.29 × L
PUHY-RP400 - RP550YSJM: 3.12× L
L : Length of ø19.05 liquid pipe (m)
1
L : Length of ø15.88 liquid pipe (m)
2
L : Length of ø12.7 liquid pipe (m)
3
L : Length of ø9.52 liquid pipe (m)
4
L : Length of ø6.35 liquid pipe (m)
5
2) When merging two refrigerant piping systems into one, make sure the length difference between the two systems is 40 m [131
ft] or less.
HWE10130
(Note1) Install the pipe that connects the branch pipe and the outdoor units in
the way that it has a downward inclination toward the branch pipe.
Downward inclination
Upward inclination
D
L
B
C
a b
Indoor Indoor
1 2
Operation
Total pipe length
Total pipe length (L) from the
outdoor unit to the farthest indoor
unit
Total pipe length from the first
branch to the farthest indoor unit
( )
Between outdoor units
Outdoor unit
above indoor
unit
Between indoor
and outdoor units
Outdoor unit
below in-
door unit
Between indoor units
Between outdoor units
+ 0.2 × L + 0.12 × L
1 2
' + 2.15 × L ' + 1.29 × L
1 2
If the piping length between the branch pipe and the
outdoor unit exceeds 2 m [6 ft] , provide a trap on the
piping (gas piping only) within 2 m [6 ft] of the branch
pipe to prevent the refrigerant oil from accumulating in
the piping and causing compressor damage.
Minimum trap height: 200 mm [7 inches]
To indoor unit
To indoor unit
Branch header
e
d
Indoor Indoor
4
5
c
Indoor
3
Pipe sections
A+B+C+D+E+F+a+b+c+d+e+f
E(F)+A+B+C+c
or E(F)+A+D+f
B+C+c
or D+f
E+F
H1
H1'
h
H2
+ 0.06 × L + 0.024 × L
3 4
' + 0.65 × L ' + 0.26 × L
3 4
L ' : Length of ø19.05 [3/4"] liquid pipe [ft]
1
L ' : Length of ø15.88 [5/8"] liquid pipe [ft]
2
L ' : Length of ø12.7 [1/2"] liquid pipe [ft]
3
L ' : Length of ø9.52 [3/8"] liquid pipe [ft]
4
L ' : Length of ø6.35 [1/4"] liquid pipe[ft]
5
- 48 -
To indoor unit
2m [6 ft]
Trap
(gas pipe
only)
To indoor unit
2m [6 ft] Max.
cap
f
Indoor
6
Allowable length of pipes
300 [984] or less (Note 1)
120 [393] or less
(Equivalent length 150 [492]or
less)
40 [131] or less (Note 2)
10 [32] or less
(Equivalent length 12 [39] or
less)
50 [164] or less
40 [131] or less
15 [49] or less
0.1 [0.3] or less
< 25 (kg)
5
' < 56 [oz]
5
Unit: m [ft]
GB