Various Protections - Fujitsu ARU7RLF Service Instruction

22. VARIOUS PROTECTIONS

1. DISCHARGE GAS TEMPERATURE OVER RISE PREVENTION CONTROL
The discharge gas thermosensor (discharge thermistor : Outdoor side) will detect discharge gas
temperature.
When the discharge temperature becomes higher than
is decreased 20rps, and it continues to decrease the frequency for 20rps every 120 seconds until
the temperature becomes lower than
When the discharge temperature becomes lower than
frequency is released.
When the discharge temperature becomes higher than
When the discharge temperature becomes lower than
(Table 19 : Discharge Temperature Over Rise Prevension Control / Release Temperature)
AOU18 / 24RLXFZ
AOU36RLXFZ
2. CURRENT RELEASE CONTROL
The compressor frequency is controlled so that the outdoor unit input current does not exceeds
the current limit value that was set up with the outdoor temperature.
The compressor frequency returns to the designated frequency of the indoor unit at the time
when the frequency becomes lower than the release value.
3. ANTI-FREEZING CONTROL (Cooling mode)
When the indoor unit heat exchanger and
2-way valve temperature becomes lower than
is decreased 20rps, and it continues to decrease the frequency for 20rps every 120 seconds until
the temperature becomes higher than
This operation is not released until both the temperature of the indoor unit heat exchanger and
2-way valve temperature exceed the release temperature.
(Table 20 : Anti-freezing Protection Operation / Release Temperature)
Outside air
Temperature
= >
53.6°F(12°C)
53.6°F(12°C)
<
.
Tenperrature Tenperrature
220°F(105°C) 203°F (95°C)
230°F(110°C) 212°F(100°C)
,the compressor frequency
.
Tenperrature
Indoor Heat Ex. 2-way valve
Temperature Temperature
37.4°F(3°C)
37.4°F(3°C)
01-29
,the compressor frequency
,the control of the compressor
,the compressor stops.
176°F(80°C) ,the compressor operates.
Tenperrature
230°F(110°C)
239°F(115°C)
Indoor Heat Ex.
Temperature
35.6°F(2°C) 42.8°F(6°C)
35.6°F(2°C) 55.4°F(13°C)
Tenperrature
2-way valve
Temperature
41.0°F(5°C)
53.6°F(12°C)