Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
Set Multimeter to Resistance 
Gain access to PCB (use Insulation Mat as required)
Remove air pressure switch for testing
Note:
If flueway sump seal is disturbed a new seal must be fitted, refer to Adapt for guidance
Remove air pressure switch for testing
Note:
If flueway sump seal is disturbed a new seal must be fitted, refer to Adapt for guidance
Measurement:
Note the operating pressure indicated on the pressure switch.
Connect the air pressure switch charge kit to P1 connection on the air pressure switch.
Measure for resistance across the normally closed terminals, slowly increase the pressure via the syringe, the air pressure switch should not go to open circuit until the pressure has reached that indicated on the pressure switch.
Connect the air pressure switch charge kit to P1 connection on the air pressure switch.
Measure for resistance across the normally closed terminals, slowly increase the pressure via the syringe, the air pressure switch should not go to open circuit until the pressure has reached that indicated on the pressure switch.
Isolate as per TOPs P4
and refit as necessary