Panasonic U-100PEY1E5, Technical Data & Service Manual, Page: 573 / 739

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4
4) Cooling High-Load Prevention Control
This system control is performed to limit the inverter frequency in order to restrict high pressure’s abnormal increase
and high-load operating prevention in the cooling mode.
In accordance with the temperature of the outdoor heat exchanger temperature sensors (C1, C2), such controls are
performed as to halting the operations of the indoor unit, decreasing the inverter frequency and restricting its increase,
etc.
When the maximum temperatures sensor (C1, C2) exceeds 64°C, operations of the indoor unit are halted and
restarted after 3 minutes.
If this start/stop activity is repeated 10 times, the alarm "P20" (cooling high-load error) occurs.
max. (C2, C1)
Outdoor unit operations halted
Frequency decreased
Frequency increases prevented
Frequency increased slower than normal
Normal operations (no control)
b
a
c
d
e
Control point
50PE 60PEY 71PEY
a
b
c
d
e 64
61
59
58
53 64
59
58
57
53 64
59
58
57
53
Control
point
a
b
c
50PE
65
54 (56)
52
60PEY
65
54 (56)
52
71PEY
65
54 (56)
52
°C
°C
max. (E1, E2)
a
b
c
5) Heating High-Load Prevention Control
This system control is performed to limit the inverter frequency in order to restrict high pressure’s abnormal increase
and high-load operating prevention in the heating mode.
In accordance with the temperature of the indoor heat exchanger temperatures sensor (E1, E2), such controls are
performed as to halting the operations of the indoor unit, decreasing the inverter frequency and restricting its increase,
etc.
When the maximum temperatures sensor (E1, E2) exceeds 65°C, the outdoor unit operation is halted and restarted
after 3 minutes.
Outdoor unit operations halted
Frequency decreased
Frequency increases prevented
Normal operations (no control)
unit :
°C
unit :
°C
SM830211-07̲PAC-i.indb 13 SM830211-07̲PAC-i.indb 13 2013/08/06 21:55:41 2013/08/06 21:55:41