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Role:
g
It monitors the loop’s High Pressure
g
It detects too low a pressure P1 < 2 bars
g
It detects too high a pressure P2 > 27 to 32 bars
g
It includes one additional threshold to activate the
maximum speed of the cooling fan P3 > 16 bars.
Pressure switch
P1
P2
low
high
medium
P3
Pressure sensor has a security function
11.9 Safety devices
11.9.1 The pressure switch (pressostat)
The pressure switch monitors the A/C loop high
pressure level; it enables or disables the compressor
according to two pressure thresholds.
One additional circuit controls the cooling fan; it
secures the condensation process by forcing the air
flow through the condenser.
The pressure switch is a safety device
for the A/C loop.
The pressure switch is located on the High
Pressure side of the loop.
11. The components
of the A/C Loop
60