Set Appliance State:
Gas On; Pilot On
CH Demand
Isolate Mains Power to appliance as per TOPs P4
Boiler Operating Switch in HW and CH position
Heating Control Thermostat (Potentiometer) adjusted to Maximum
Connect a U-gauge to the Gas Valve outlet pressure test point
CH Temperature selector on Maximum
Boiler Operating Switch in HW and CH position
Heating Control Thermostat (Potentiometer) adjusted to Maximum
Connect a U-gauge to the Gas Valve outlet pressure test point
CH Temperature selector on Maximum
| WARNING! Mains voltage is expected during test, follow TOPs P4 live testing procedure |
Measurement:
Allow the burner to cross-light from the pilot.
Does the burner ignite to its pre-set pressure?
When boiler has reached a reasonable operating temperature turn down the heating control thermostat.
Does the burner gas pressure reduce with boiler temperature and control thermostat demand?
Notes:
It may be necessary to reduce the heating load by turning off some radiators to reduce time taken for this test.
If boiler is set at its minimum CH output modulation will not take place.
When U-gauge is removed pressure test point should be tightened & checked for gas soundness.
Does the burner ignite to its pre-set pressure?
When boiler has reached a reasonable operating temperature turn down the heating control thermostat.
Does the burner gas pressure reduce with boiler temperature and control thermostat demand?
Notes:
It may be necessary to reduce the heating load by turning off some radiators to reduce time taken for this test.
If boiler is set at its minimum CH output modulation will not take place.
When U-gauge is removed pressure test point should be tightened & checked for gas soundness.
Isolate as per TOPs P4
and refit as necessary