Mitsubishi Heavy Industries SRK25GZ-L1 Handbook page 560

FDR-H
Table of bypass factor
Model
FDR 208 type
Item
Hi
Air flow
Lo
(2) Correction of cooling and heating capacity in relation to air flow rate control (fan speed)
Coefficient: 1.00 at High, 0.95 at Low
(3) Correction of cooling and heating capacity in relation to one way length of refrigerant piping
It is necessary to correct the cooling and heating capacity in relation to the one way equivalent piping length between the indoor
and outdoor units.
(1)
Equivalent piping length m
Heating
FDR208 type
FDR258 type
FDR308 type
(FDC308 type)
FDR408 type
(FDC408 type)
FDR508 type
(FDC508 type)
FDR508 type
(FDC306 type)
FDR408 type
(FDC406 type)
FDR508 type
(FDC506 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 and when the
outdoor unit is located at a higher height than the indoor unit in heating 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
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 and heating capacity
Example : The net cooling capacity of the model FDR308HEN-SA 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 =
558
FDR 258 type
0.035 0.032
0.021 0.020
5 10 15
1.0 1.0 1.0
1.0 0.995 0.995
1.0 0.995 0.99
1.0 0.99
0.98
1.0
0.995 0.985
1.0
0.99 0.975
1.0 0.99 0.98
1.0 0.995 0.985
1.0 0.99 0.975
Model FDR208, 258 type
30m
Outdoor unit is higher 20m
Outdoor unit is lower 15m
×
7100 1.00
FDR308HEN-SA Air flow
"High"
FDR 308 type
0.039
0.023
20 25 30 35
1.0 1.0 0.995 0.995
0.99 0.985 0.985 0.98
0.985 0.98 0.975 0.97
0.97 0.96 0.95 0.94
0.98 0.97 0.965 0.955
0.965 0.95 0.94 0.925
0.97 0.96 0.95 0.94
0.98 0.97 0.965 0.955
0.965 0.95 0.94 0.925
5m 10m 15m
0.01 0.02 0.03
FDR308~508 type
(FDC308~508 type)
50m
Outdoor unit is higher 30m
Outdoor unit is lower 15m
× ×
(0.98 - 0.01)
Length 15m.
Height difference 5 m
FDR 408 type FDR 508 type
0.085 0.035
0.060 0.023
40 45 50
0.99 0.99 0.985
  
  
0.93 0.92 0.91
0.95 0.94 0.935
0.915 0.9 0.89
  
  
  
20m 25m
0.04 0.05
FDR308~508 type
(FDC306~506 type)
30m
15m
1.0 = 6887 w
Factor by air
temperatures
55
0.985


0.9
0.925
0.875



30m
0.06