Sanyo Big PACi 18 Series Technical Data & Service Manual page 207

5) Heating High-Load Prevention Control
The following control is performed in the heating mode in accordance with the indoor heat exchanger temperature
max (E1, E2). (See the chart below.)
(1) The operational frequency of the compressor is decreased when the temperature enters the "M" zone.
The operation frequency is modified every 30 seconds while the temperature remains in this zone
(the thermostat is switched off if it continues for 2 minutes).
(2) The "N" zone is the area in which operation frequency increases are prevented.
(3) The operational frequency returns to normal control when the detected temperature enters the "L" zone.
max. (E1, E2)
Thermostat OFF
58
53(52)
( * )
48
* During the increase of temperature max (E1, E2) after the compressor is switched on, the temperature
for entering the "M" zone for the first time is set at 52
The temperature for entering the "M" zone is reset to 52
4
less than 30
6) Cooling Freeze Prevention Control
The following control is performed during cooling operations (including dehumidifying operation), in accordance
with whichever of the indoor heat exchanger temperatures (E1 or E2) is lower. (See the chart below.)
(1) If the temperature remains in the "J" zone (decreasing operation frequency and thermostat OFF zone) for
6 minutes, the operating frequency of the compressor is decreased.
The operation frequency is amended every 30 seconds as long as the temperature is in this zone.
(2) If the temperature is in the "K" zone (operating frequency increase prevention zone), the operating
frequency of the compressor is maintained.
(3) If the temperature is in the "H" zone (operating frequency restriction zone) and the outdoor air temperature
is less than 32
indoor unit fan speed.
(4) If the temperature is in the "I" zone (normal operation zone), normal operations are performed.
(5) If the temperature is continuously in the "J" zone with the compressor's operating frequency reaches "0",
then temperature A, which is temperature for changing from the "J" zone to the "H" zone, is raised from
5 to 8 , and operation continues with the thermostat off until the temperature enters the "H" zone.
E1 (or E2)
22
17
5
2
M
N (operational frequency increase prevention zone)
L
.
, the maximum operating frequency of the compressor is limited in accordance with the
I
H
K (operating frequency increase prevention zone)
J
.
after the temperature max (E1, E2) dropped
A
4-4