Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Remove connector M5 from the PCB
Remove tube from front connector of APS
Remove tube from front connector of APS
Measurement:
Note the operating pressure indicated on the pressure switch.
Connect the air pressure switch charge kit to +ve connection on the air pressure switch (rear connector of APS)
Increase the pressure via the syringe to that indicated on the pressure switch.
Measure the resistance between pins 14 and 15 on connector M5.
Expect continuity or zero resistance.
Note:
If continuity is not obtained when the specified pressure
is applied it is permissible to increase the pressure by 50%
100 Pascals = 1mbar / 50 Pascals = 0.5mbar
Connect the air pressure switch charge kit to +ve connection on the air pressure switch (rear connector of APS)
Increase the pressure via the syringe to that indicated on the pressure switch.
Measure the resistance between pins 14 and 15 on connector M5.
Expect continuity or zero resistance.
Note:
If continuity is not obtained when the specified pressure
is applied it is permissible to increase the pressure by 50%
100 Pascals = 1mbar / 50 Pascals = 0.5mbar
Isolate as per TOPs P4
and refit as necessary