Set Appliance State:

CH Demand
DHW Demand
DHW Temperature Control on MAX
CH Temperature Control on MAX
Run DHW tap and allow a flow rate of 8l/min to run for 10mins
Then run CH and allow to run until boiler temperature is satisfied
NOTE:System will reach temperature quicker if you reduce the load by turning off some radiators
WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure
Mains Power On

Observation:

Does boiler run up to and at its maximum operating temperature without overheating again?