Set Appliance State:
Mains Power Off
Set Multimeter to DC Volts 
Turn Hot Water Tap On
Selector switch in OFF position
CH temperature selector to minimum
DHW temperature selector to maximum
Set flow rate at tap to approximately 5 l/min
CH temperature selector to minimum
DHW temperature selector to maximum
Set flow rate at tap to approximately 5 l/min
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
With hot water tap on, turn selector switch to the water heating position.
Allow the burner to ignite and, after approximately 3 to 4 seconds, go to maximum
burner pressure (approximately 12.5mb).
While slowly turning down the DHW temperature selector, measure the voltage across the terminals of the modulating solenoid.
Does the voltage reduce as the temperature demand is met?
Allow the burner to ignite and, after approximately 3 to 4 seconds, go to maximum
burner pressure (approximately 12.5mb).
While slowly turning down the DHW temperature selector, measure the voltage across the terminals of the modulating solenoid.
Does the voltage reduce as the temperature demand is met?
