Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 395

(3) Correction of cooling capacity in relation to one way length of refrigerant piping
It is necessary to correct the cooling capacity in relation to the one way equivalent piping length between the indoor and outdoor
units.
Equivalent piping length (1) m
FDTNP, FDT208 type
FDTNP, FDT258 type
FDTNP308 type
FDTNP408 type
FDTNP508 type
FDT308 type
FDT408 type
FDT508 type
Note (1) Equivalent piping length can be obtained by calculating as follows.
208, 258, 308 series [φ15.88(5/8")]: Equivalent piping length = Real piping length + (0.10 × Number or bends in piping)
408, 508, series [φ19.05(3/4")]: Equivalent piping length = Real piping length + (0.15 × Number of bends in piping)
[Equivalent piping length < Limitation length of piping + 5m]
(4) When the outdoor unit is located at a lower height than the indoor unit in cooling operation, the following values
should be subtracted from the values in the above table.
Height difference between the indoor unit and
outdoor unit in the vertical height difference
Adjustment coefficient
Piping length limitations
Modei
Item
Max.one way piping length
Max.vertical height difference
Note (1) Values in the table indicate the one way piping length between the indoor and outdoor units.
How to obtain the cooling capacity
Example : The net cooling capacity of the model FDT308CEN-A with the air flow "High", the piping length of 15m, the outdoor unit
located 5m lower than the indoor unit, indoor wet-bulb temperature at 19.0 ˚C and outdoor dry-bulb temperature 35 ˚C is
Net cooling capacity =
5 10 15 20
0.995 0.99
1.0 0.995
1.0 0.995 0.99 0.985
1.0 0.99
0.98 0.97
1.0
0.995 0.985 0.98
1.0
0.99 0.975 0.965
0.98 0.97
1.0 0.99
/0.975 /0.965
0.995 0.985 0.98
1.0
/0.99 /0.98 /0.97
0.99 0.975 0.965
1.0
/0.985 /0.97 /0.955
FDT208, 258
FDTNP208, 258 type
20m(Outdoor unit is higher)
15m(Outdoor unit is lower)
×
7100 1.00
Air flow
FDT308CEN-A
"High"
25 30 35
0.985 0.985 0.98
0.98 0.975 0.97
0.96 0.95 0.94
0.97 0.965 0.955
0.95 0.94 0.925
0.96 0.95 0.94
/0.95 /0.94 /0.925
0.97 0.965 0.955
/0.96 /0.95 /0.94
0.95 0.94 0.925
/0.94 /0.925 /0.91
5m 10m
0.01 0.02
FDT308~508 type
30m
15m
× ×
(0.98 - 0.01)
Length 15m.
Height difference 5 m
FDT ( N ) -C
50/60Hz
40 45 50 55
   
   
0.93 0.92 0.91 0.9
0.95 0.94 0.935 0.925
0.915 0.9 0.89 0.875
   
   
   
15m
0.03
FDTNP308~508 type
50m
30m(Outdoor unit is higher)
15m(Outdoor unit is lower)
1.0 = 6887 w
Factor by air
temperatures
393