Mitsubishi Electric CMB-WM108V-AA Service Handbook page 136

[ VII Test Run Mode ]
(1) Calculation formula (PURY-(E)M)
The amount of refrigerant to be added depends on the size and the length of field piping. (unit in m[ft])
1) When the distance between HBC and outdoor unit is longer than 10m:
Amount of added refrigerant (kg) = (0.09xL
2) When the distance between HBC and outdoor unit is 10m or shorter:
Amount of added refrigerant (kg) = (0.11xL
L :Length of Φ15.88 [5/8"] high pressure pip (m)
1
α :Refer to the table below.
1
Outdoor unit index
(Heat source unit model)
(E)M200
(E)M250
(E)M300
Amount for the HBC controller
α (kg)
1
2.8
Round up the calculation result to the nearest 0.1kg. (Example: 18.04kg to 18.1kg)
(2) Example
Outdoor unit
(~(E)M300) (Heat source unit)
A
Indoor unit
(10 ~ 50)
Outdoor unit
A
HWE1708A
)+α
1 1
)+α
1 1
Diameter of
high-pressure pipe
ø15.88
ø15.88
ø15.88
HBC controller
Indoor unit Indoor unit
(10 ~ 50) (10 ~ 50)
(~(E)M300) (Heat source unit)
B
HBC controller
C
D
HBC controller
Indoor unit Indoor unit
(10 ~ 50) (10 ~ 50)
(3) Sample calculation
Indoor
Outdoor
Indoor unit
(10 ~ 50)
The total length of each liquid line is as follows:
ø15.88: A = 42 m,
Therefore,
<Calculation example>
Additional refrigerant charge
= 42 × 0.09 + 2.8
= 6.58 kg
= 6.6 kg
* All pipe work except A is water pipe work.
Indoor
Indoor unit
Outdoor
(10 ~ 50)
The total length of each liquid line is as follows:
Indoor unit
ø15.88: A = 18 m, ø15.88: B + C + D = 23m,
(10 ~ 50)
Therefore,
<Calculation example>
Additional refrigerant charge
= (18 + 5 + 10 + 8) × 0.11 + 2.8 × 2
= 9.56 kg
= 9.6 kg
* All pipe work except A, B, C, D is water pipe work.
- 127 -
1: 50 A: ø19.05 42 m
2: 50
3: 50
4: 40
P250
= 2.8
α
1
1: 50 A:ø22.2 18 m
2: 50 B:ø15.88 5 m
3: 50 C:ø15.88 10 m
4: 50 D:ø15.88 8 m
P400
α = 2.8 × 2
1
GB