Set Appliance State:

Mains Power Off

Observation:

Increase the system pressure slightly whilst observing the
gauge on the front of the appliance.
The gauge should respond to the increase in system pressure.
Does the pressure gauge respond to the increase in system pressure?
Note:
Ensure the system pressure is correctly set at between 1 and 1.5 bar
when the appliance and system are cold before moving onto next test.