Set Appliance State:
Gas Off
Set Multimeter to AC Volts 
Isolate Mains Power to appliance as per TOPs P4
Ensure that DHW is calling for heat
Remove all three APS wires, link them all together then position in a safe location
(Do not hold the wires or allow them to touch the case)
Ensure that DHW is calling for heat
Remove all three APS wires, link them all together then position in a safe location
(Do not hold the wires or allow them to touch the case)
| WARNING! - Mains voltage is expected during test follow TOPs P4 live testing procedure |
Measurement:
User control switch to ON position.
Allow the appliance to commence its Ignition Sequence
Does sparking now occur?
Note:
After test remove any links and re-fit wires
on to air pressure switch in the correct position.
Allow the appliance to commence its Ignition Sequence
Does sparking now occur?
Note:
After test remove any links and re-fit wires
on to air pressure switch in the correct position.
Isolate as per TOPs P4
and refit as necessary