Mitsubishi Electric MXZ-8B48NA, Technical & Service Manual, Page: 32 / 88

32
5-2-2. Correcting Capacity for Changes in the Length of Refrigerant Piping
To obtain the ratio (and the corrected piping length) of the outdoor units Max. capacity and the total in-use indoor capacity, first
find the capacity ratio corresponding to the standard piping length from Fig.3, Fig.4 and then multiply by the capacity from Fig.
1-1, 1-2, Fig. 2-1, 2-2 to obtain the actual capacity.
(1) Capacity correction factor
(2) Method for Obtaining the Corrected Piping Length
Corrected piping length = (Actual piping length between outdoor unit and the farthest indoor unit) + (0.30
o
number of bends in the
piping) (m), (ft)
Fig. 3 Cooling capacity correction curve
9 (11.1%)
27 (50%)
40.5 (75%)
54.0 (100%)
70.2 (130%)
0.65
20 40 60 80 (m)
20 40 60 80
0.70
0.75
0.80
0.85
0.90
0.95
1.00
70 130 195 260 (ft)
Cooling
Capacity
(ratio)
[%]
Total rated capacity of indoor units (kBTU/h)
Corrected piping length
0.9
20 40 60 80 (m)
0.95
1
70 130 195 260 (ft)
Heating
Capacity
(ratio)
[%]
Corrected piping length
Fig. 4 Heating capacity correction curve