21
7425MUM651
Model: QBS
- Use and Maintenance Manual
Rev. 02
6.2
R
EARMING THE HIGH
-
PRESSURE PRESSURE SWITCH
The intervention of the high-pressure pressure switch is the only case in which, in addition to
manually rearming the electronic controller, it is also necessary to reset the pressure switch itself.
The high-pressure pressure switch is located in the compressor compartment on the uninsulated
copper pipe that goes from the compressors to the condensation coil; there is a manual-reset button on
top of it.
Warning!
The upper part of the compressor casing and discharge pipe are at a high
temperature.
Be especially careful when working in their vicinity.
This can only be rearmed when the pressure in the circuit has fallen below the reset value (see table
Calibration of the safety devices and type of rearm
in paragraph 6.1).
High pressure switch
For this reason, when dealing with an intervention of the high-pressure
switch, it is necessary to:
A)
Identify the cause of the rise in pressure (fan not working,
condensation coil dirty or obstructed, obstacles to the flow of
exiting air, operating temperature outside operating limits, etc.
(also see Chapter
9 Troubleshooting
) and remove the cause, if
possible;
B)
Wait until the high-pressure manometer falls below the reset
value (see the table,
“Calibration of the safety devices and type
of rearm”
in paragraph 6.1);
C)
Rearm the pressure switch by pressing the red button: if you do
not hear a click, it is not rearmed;
D)
Then rearm the electronic controller.
Attention!
The high-pressure gauge stops the compressor while it keeps the condenser fan
running to lower the pressure in the condenser.