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5
2
A
J
K
I
[˚C]
No.
8
Item
Freeze preventive control
(Low temperature release)
Outline of specifications
1) The cooling operation (including Dry operation) is
performed as follows based on the detected
temperature of Tc sensor or Tcj sensor.
When [J] zone is detected for 6 minutes
(Following figure), the commanded frequency is
decreased from the real operation frequency.
After then the commanded frequency changes every
30 seconds while operation is performed in [J] zone.
In [K] zone, time counting is interrupted and the
operation is held.
When [ I ] zone is detected, the timer is cleared and
the operation returns to the normal operation.
If the commanded frequency becomes S0 because
the operation continues in [J] zone, the return
temperature A is raised from 41°F (5°C) to
53.6°F (12°C) until [ I ] zone is detected and the
indoor fan operates with [L] mode.
In heating operation, the freeze-preventive control
works if 4-way valve is not exchanged and the
following conditions are satisfied.
(However the temperature for J zone dashing control is
changed from 35.6°F (2°C) to 23°F (–5°C.))
<Conditions>
• When
Q
or
R
is established 5 minutes after
activation.
Q
Tcn
≤
Tc (n – 1) – 5
R
Tcn < Tc (n – 1) – 1 and Tcn
≤
Ta < 41°F (5°C)
Remarks
Tcj:
Indoor heat exchanger
sensor temperature
Tcn:
Tc temperature when
5 minutes elapsed
after activation
Tc (n – 1):
Tc temperature at
start time
9
High-temp. release
control
1) The heating operation is performed as follows based on the detected temperature
of Tc sensor or Tcj sensor.
• When [M] zone is detected, the commanded frequency is decreased from the
real operation frequency. After then the commanded frequency changes every
30 seconds while operation is performed in [M] zone.
• In [N] zone, the commanded frequency is held.
• When [L] zone is detected, the commanded frequency is returned to the original
value by approx. 6Hz every 60 seconds.
Setup at shipment
A
B
L
N
M
Tc, Tcj
˚F [˚C]
Control temp. °F (°C)
A
B
132.8 (56)
125.6 (52)
(129.2 (54))
(125.6 (52))
NOTE:
When the operation has started or when Tc or Tcj < 86°F (30°C) at start of the
operation or after operation start, temperature is controlled between values in
parentheses of A and B.