fiac TDRY 6-18 Manuel D'instructions page 54

As operation safety and protection of the dryer a series of pressure switches are installed in the gas circuit.
PB : Low-pressure controller device on the suction side (carter) of the compressor, is enabled only if the
pressure drops below the pre-set value. The values are automatically reset when the nominal
conditions are restored.
Calibrated pressure : R 404 A Stop 1.0 barg - Restart 5.0 barg
This high-pressure controller device is located at the pushing side of refrigeration compressor, and
PA :
it is activated when the pressure exceeds the pre-set value. It features a manual-resetting button
mounted on the controller itself.
Calibrated pressure : R 404 A Stop 32 barg - Manual reset
Fan control pressure switch located on the pushing side of the compressor. It keeps the
PV :
condensation temperature/pressure constant within preset limits (Air-Cooled).
Calibrated pressure : R 134.a Start 11 barg (47°C) - Stop 8 barg (36°C) - Tolerance ± 1 bar
Pos. 1
5.13 REFRIGERANT PRESSURE SWITCH PA - PB - PV
R 404 A Start 20 barg (45°C) - Stop 16 barg (36°C) - Tolerance ± 1 bar
5.14 SAFETY THERMO-SWITCH T
To protect the operating safety and the integrity of the dryer, a thermo-
switch (T ) is installed on the refrigerant gas circuit. The thermo-switch
S
sensor, in case of unusual supply temperatures, stops the cooling
compressor before it is permanently damaged.
Manually reset the thermo-switch only after the nominal operating
T :
S
conditions have been restored. Unscrew the relative cap (see pos.1
Pos. 2
in the figure) and press the reset button (see pos.2 in the figure).
S
GB