Fujitsu R407C User Manual

1. Central discharge temperature protection
1) When the discharge temperature of any compressor reaches 110 C or higher, solenoid valve 1 (SV1)
is turned on and bypass is performed. SV1 is turned off and central discharge temperature protection
operation is ended by any of the following conditions:
(1) Discharge temperature of all compressors reaches 95 C or lower.
(2) Oil recovery operation starts.
2) When solenoid valve 1 (SV1) is on and the outdoor fan speed is "5"(about fan speed, please refer to 3-3),
solenoid valve 2 (SV2) is simultaneously turned on and bypass is performed. SV2 is turned off by any of
the following conditions:
(1) Outdoor fan speed is set to other than "5".
(2) Oil recovery operation starts.
(3) Discharge temperature of all compressors reaches 95 C or lower.
2. Discharge temperature protection
3. High-pressure protection
1) When the high-pressure SW (HP) is turned off except during oil recovery operation or defrosting,
solenoid 1 (SV1) and solenoid 2 (SV2) are turned on and bypass is performed. SV1 and SV2 are turned
off by any of the following conditions:
(1) High-pressure pressure SW turned on.
(2) Oil recovery control starts.
(3) Defrosting control starts.
2) When 1 minute has elapsed after SV1 and SV2 were turned on and the discharge pressure sensor
detected value is 3.34MPa or higher, compressors 1, 2, and 3 are stopped. SV1 and SV2 ON and
compressors 1, 2, and 3 stop are reset and high-pressure protection operation is ended by any of the
following conditions:
(1) High-pressure SW turned on.
(2) Oil recovery control starts.
(3) Defrosting control starts.
4. Heating overload protection
When the operating mode is " Heating " and the high-pressure SW was turned off except during oil recovery or
defrosting in the "Heat mode", the outdoor fan is stopped. Outdoor fan stop is reset and heat overload protection
operation is ended by any of the following conditions:
(1) High-pressure SW turned on.
(2) Oil recovery control starts.
(3) Defrosting control starts.
(4) Mode is switched to other than "Heat".
When the discharge temperature of any compressor reaches 130 C or higher, the corresponding compressor
stops. Compressor stop is reset and discharge temperature protection operation is ended by any of the following
conditions:
(1) Discharge temperature of all compressors reaches 95 C or lower.
(2) Oil recovery operation starts.
However, during oil recovery operation, discharge temperature protection is not performed.
3-10 PROTECTION FUNCTIONS
03-11

Fujitsu R407C Specifications

General

Brand	Fujitsu
Model	R407C
Category	Air Conditioner
Language	English