Piping Length Limitations; How To Obtain The Cooling And Heating Capacity - Mitsubishi Heavy Industries FDTCVA SERIES Technical Manual

± Ambient air temperature -5°C
Equivalent piping length
Heating
802 model
1002 model
802 model
Cooling
1002 model
802 model
1002 model
± Ambient air temperature -15°C
Equivalent piping length
Heating
802 model
1002 model
802 model
Cooling
1002 model
802 model
1002 model
Note (1) Calculate the equivalent length using the following formula.
However, install the piping so that the piping length is within +5 m of the limit length (actual length) for the respective types.
• Equivalent Length = Actual Length + (Equivalent bend length x number of bends in the piping.)
Equivalent length per bend.
Gas Pipe Diameter (mm)
Equivalent Bend Length
(5) When the outdoor unit is located below indoor units in cooling mode, or when the outdoor unit is located above indoor units in
heating mode, the correction coefficient mentioned in the below table should be subtracted from the value 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
Notes (1) Values in the table indicate the one way piping length between the indoor and outdoor units.
When φ22.22 gas pipe is applied to 802 and 1002 (*mark), maximum one way length is limited to 30m.
(2)

How to obtain the cooling and heating capacity

Example : The net cooling capacity of the model FDUMVA402HEN2R with the air fl ow "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 =
FDUMVA402HEN2R
Note (1) The above conditions show calculations for when the outside air temperature is 5°C or higher and the gas pipe size is φ15.88.
The capacity correction coefficient will differ depending on the proportions between the outside air temperature and the gas pipe size.
(1) (m) 7.5 10 15
1 0.998 0.995 0.991 0.988 0.984 0.981 0.977 0.974 0.970 0.967 0.963 0.960 0.956 0.953
1 0.993 0.979 0.965 0.950 0.936 0.922 0.908 0.894 0.880 0.866
φ25.4
1 0.991 0.974 0.958 0.941 0.925 0.908 0.891 0.875 0.858 0.841
0.993 0.985 0.968 0.951 0.934 0.917 0.899
φ22.22
0.988 0.978 0.957 0.937 0.916 0.895 0.875
1.003 0.996 0.984 0.971 0.958 0.946 0.933 0.921 0.908 0.896 0.883
φ28.58
1.004 0.997 0.983 0.969 0.955 0.941 0.927 0.913 0.899 0.885 0.870
(1) (m) 7.5 10 15
1 0.998 0.995 0.991 0.988 0.984 0.981 0.977 0.974 0.970 0.967 0.963 0.960 0.956 0.953
1 0.987 0.963 0.938 0.913 0.889 0.864 0.839 0.815 0.790 0.765
φ25.4
1 0.986 0.959 0.932 0.904 0.877 0.850 0.823 0.795 0.768 0.741
0.993 0.980 0.952 0.924 0.897 0.869 0.841
φ22.22
0.988 0.973 0.941 0.910 0.879 0.848 0.817
1.003 0.991 0.968 0.945 0.921 0.898 0.875 0.852 0.829 0.806 0.782
φ28.58
1.004 0.992 0.967 0.943 0.918 0.893 0.869 0.844 0.819 0.795 0.770
φ15.88
0.25
Model
×
10.0 1.00
Air fl ow
"High"
20 25 30 35
20 25 30 35
φ22.22 φ25.4 φ28.58
0.35 0.40 0.45
5m 10m
0.01 0.02
151~251 302, 402, 502, 602
40m
Outdoor unit is higher 30m
×
(0.978 (1) - 0.01)
Length 15m.
Height difference 5m
136
- -
40 45 50 55 60
0.852
0.825
– – – – –
– – – – –
0.870
0.856
40 45 50 55 60
0.741
0.713
– – – – –
– – – – –
0.759
0.745
15m 20m
0.03 0.04
50m
Outdoor unit is lower 15m
× ≈
1.0 9.7 kW
Factor by air
temperatures
65 70 75
0.838 0.824 0.810
0.808 0.791 0.775
– – –
– – –
0.858 0.845 0.833
0.842 0.828 0.814
65 70 75
0.716 0.691 0.667
0.686 0.659 0.631
– – –
– – –
0.736 0.713 0.690
0.720 0.696 0.671
25m 30m
0.05 0.06
802, 1002
70m*