Set Appliance State:

Access level 2 diagnostics as in the previous test.
Gas On
WARNING! - Mains voltage is expected during test follow
TOPs P4 live testing procedure
Mains Power On

Observation:

The DS number can be disrupted if the power to the boiler is isolated or reset too soon after being switched on. To avoid this wait at least 60 seconds between power off/on, and or reset.
The DS number can be changed by pressing + or - when the value is displayed.
Select the number that corresponds with your model.
Press and hold MODE for 5 seconds to confirm.
To exit the diagnostic menu, press the MODE and + buttons
at any time.
Once the DS number has been adjusted recheck the appliance.
Has the fault been rectified?
DS NUMBER SET CORRECTLY AND FAULT RECTIFIED
DS NUMBER SET CORRECTLY BUT FAULT STILL PRESENT
DS NUMBER CANNOT BE SET