Set Appliance State:

Mains Power Off
CH Demand
Place temperature clamps on flow and return pipes as shown
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

Reset appliance as necessary and allow the boiler to
complete its self check.
Allow CH to operate and reach a reasonable
operating temperature, approximately 55°C.
Measure the differential across the primary heat exchanger.
Differential should be approximately 20°C or less.
Note:
1. CH operation may take several minutes to ramp up to Max.
2. Initial temperature differential may be greater than 20°C when system is heated from cold, but should start to reduce as the return temperature rises.