Set Appliance State:
| Isolate Mains Power to appliance as per TOPs P4 |
CH Demand
Selector Switch in CH CONTINUOUS position
Connect a U-Gauge to the Gas Valve outlet pressure test point
CH Potentiometer (Boiler thermostat) to Maximum
Connect a U-Gauge to the Gas Valve outlet pressure test point
CH Potentiometer (Boiler thermostat) to Maximum
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
When the boiler has reached a reasonable working temperature turn the CH Potentiometer down.
Does the burner gas pressure vary between its set burner pressure and 2.5 mb
with the boiler temperature and CH potentiometer (Boiler Thermostat) demand?
Notes:
1.If the boiler has been set at its lowest output modulation will not take place.
It may be necessary to reduce the heating load by turning off some radiators to reduce time taken for this test.
2. There will be a delay of between 1 and 3 mins before boiler starts if power has been switched off or CH demand has been interrupted.
3. When U-gauge is removed pressure test point should be tightened & checked for gas soundness.
Does the burner gas pressure vary between its set burner pressure and 2.5 mb
with the boiler temperature and CH potentiometer (Boiler Thermostat) demand?
Notes:
1.If the boiler has been set at its lowest output modulation will not take place.
It may be necessary to reduce the heating load by turning off some radiators to reduce time taken for this test.
2. There will be a delay of between 1 and 3 mins before boiler starts if power has been switched off or CH demand has been interrupted.
| Isolate Mains Power to appliance as per TOP's P4 |
Isolate as per TOPs P4
and refit as necessary