Set Appliance State:
CH Demand
Isolate Mains Power to appliance as per TOPs P4
Selector switch to Heating & Water
Attach a U-gauge to gas valve
CH control potentiometer (1) to maximum
Selector switch to Heating & Water
Attach a U-gauge to gas valve
CH control potentiometer (1) to maximum
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Allow boiler to fire and burner pressure to ramp up to its set CH pressure.
When system has reached a reasonable temperature slowly turn down
the CH control potentiometer.
Does the burner pressure reduce as the temperature demand is met?
Notes:
Pressure ramp up or modulation will not take place if CH system is satisfied with boiler on low rate, this is normal operation.
When U-gauge is removed pressure test point should be tightened & checked for gas soundness.
When system has reached a reasonable temperature slowly turn down
the CH control potentiometer.
Does the burner pressure reduce as the temperature demand is met?
Notes:
Pressure ramp up or modulation will not take place if CH system is satisfied with boiler on low rate, this is normal operation.
When U-gauge is removed pressure test point should be tightened & checked for gas soundness.
Isolate as per TOPs P4
and refit as necessary