Correction At Frost And Defrost; (Cooling) (Heating) - Mitsubishi Electric PUHY-P-YJM-A Data Book

(2) Correction at frost and defrost

Due to frost at the outdoor heat exchanger and the automatic defrost operation, the heating capacity of the outdoor unit can be
calculated by multiplying the correction factor shown in the table below.
Table of correction factor at frost and defrost
Outdoor inlet air temp. ˚C
Outdoor inlet air temp. ˚F
PUHY-P250YJM-A (-BS)
PUHY-P500YSJM-A (-BS)
PUHY-P750YSJM-A (-BS)
(3) Correction by refrigerant piping length
• PFAV-P250VM-E + PUHY-P250YJM-A
PFAV-P300VM-E-F + PUHY-P250YJM-A
• Cooling
1.00
0.95
0.90
0.85
0.80
0.75
0.70
0.65
0 20 40
• Heating
1.00
0.98
0.96
0.94
0.92
0.90
0 20 40
• How to obtain the equivalent piping length
Equivalent length = (Actual piping length to the farthest indoor unit)
+ (0.42 x number of bends in the piping) m
• PFAV-P750VM-E + PUHY-P750YSJM-A
PFAV-P900VM-E-F + PUHY-P750YSJM-A
• Cooling
1.00
0.95
0.90
0.85
0.80
0.75
0.70
0.65
0 20 40
• Heating
1.00
0.98
0.96
0.94
0.92
0.90
0 20 40
• How to obtain the equivalent piping length
Equivalent length = (Actual piping length to the farthest indoor unit)
+ (0.70 x number of bends in the piping) m
6 4 2
43 39 36
1. 00 0.95 0.84
1.00 0.98 0.89
1.00 0.98 0.89
60 80 100 120 140 160 180
Piping equivalent length (m)
60 80 100 120 140 160 180
Piping equivalent length (m)
60 80 100 120 140 160 180
Piping equivalent length (m)
60 80 100 120 140 160 180
Piping equivalent length (m)
1 0 -2 -4
34 32 28 25
0.825 0.83 0.87 0.90
0.86 0.89 0.90 0.92
0.88 0.89 0.90 0.92
• PFAV-P500VM-E + PUHY-P500YSJM-A
PFAV-P600VM-E-F + PUHY-P500YSJM-A
• Cooling
1.00
0.95
0.90
0.85
0.80
0.75
0.70
0.65
0 20
• Heating
1.00
0.98
0.96
0.94
0.92
0.90
0 20
• How to obtain the equivalent piping length
Equivalent length = (Actual piping length to the farthest indoor unit)
54
-6 -8 -10 -20
21 18 14 -4
0.95 0.95 0.95 0.95
0.95 0.95 0.95 0.95
0.95 0.95 0.95 0.95
40 60 80 100 120 140 160
Piping equivalent length (m)
40 60 80 100 120 140 160
Piping equivalent length (m)
+ (0.50 x number of bends in the piping) m
180
180