Set Appliance State:
Mains Power Off
Set Multimeter to DC Volts 
DHW Demand
DHW Selector in Maximum (+) position
CH Selector in Minimum (-) position
ON/OFF Switch in ON position
DHW Selector in Maximum (+) position
CH Selector in Minimum (-) position
ON/OFF Switch in ON position
Set flow rate at tap to approximately 5 l/min
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Allow the fan to run and, after approximately 3 to 4 seconds, the burner to ignite to maximum pressure.
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?
Expect approximate voltages of 16 VDC on full demand,
modulating down to approximately 8 VDC on lower demand.
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?
Expect approximate voltages of 16 VDC on full demand,
modulating down to approximately 8 VDC on lower demand.
