FRIULAIR PURESTREAM CHILLERS CWE-Q 041, Use And Maintenance Manual

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7425MUM753 Model: CWE-Q - Use and Maintenance Manual Rev. 15
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 condensing coils; there is a
manual-rearm button on top of it. 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 7.1).
2 – Safety valve
14 – High pressure switch
1 – Pressure transducer
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 (fans not working, condensing coil dirty or
obstructed, obstacles to the flow of exiting air, operating temperature outside
operating limits, etc. – also see Chapter
10 Troubleshooting
) and remove the cause,
if possible;
B) Wait until the high-pressure gauge 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: follow the procedure as described in paragraph
5.7.1 Displaying and resetting alarms .
Caution! The high pressure gauge stops the compressor whereas the condenser
fans continue to operate to lower their internal pressure.