6 Commissioning

Turn the control thermostat knob to “O” and isolate the boilerfrom the electrical supply.Fit the combustion chamber front.Reconnect the ignition lead to the PCB.Stick the self adhesive arrow indicator to the data label, againstthe rating that the boiler is going to be set to, for future reference. The arrow is in the loose items pack.Loosen the main burner pressure test point screw and connecta suitable pressure gauge, see diagram 6.2.Make sure that any remote controls are calling for heat. Switch on/connect the electrical supply to the boiler and heatingsystem, neon 1 will light.
4138

VIEWINGWINDOWSECURINGSCREW (4)

6.4 Testing - Electrical

Turn the boiler thermostat knob fully clockwise to the maximum setting, which is about 82
o C (180
o F), neon 2 will light.The lighting sequence is automatic as follows:-The fan operates The spark ignition operates The pilot solenoid opens The pilot burner lightsThe ignition spark stopsThe main solenoid opensand after a short period of time the main burner will light, lookthrough viewing window, see diagram 6.3.Very cold weather may delay the operating sequence.The main burner will stay alight until switched off, either by thecontrol thermostat or a remote system control.To make sure that the flame supervision device is workingcorrectly the following should be done.1. With the main burner alight, turn the gas service cock “Off”,see diagram 6.1.After a short period the main burner and pilot will go out. 2. The correct working of the flame supervision device is shownby neon 4 going out within 10 seconds and the ignition starting up.Neons 1, 2 and 3 should stay alight.3. If the above does not happen, refer to fault finding Section9.1.4. To carry on turn the gas service cock “On”, see diagram 6.1.When the boiler switches “Off”, both the pilot and main burnergo out. The automatic lighting sequence will work again when heat is required.If an external control switches the boiler off, the pump will run onfor a predetermined time.

Diagram 6.3 Diagram 6.4

neon 3 will light
41464139 neon 4 will light Should any doubt exist about the gas rate, check it using the gasmeter test dial and stop watch, at least 10 minutes after the burner has lit, making sure that all other gas burning appliances and pilot lights are off. 10 to 20mm FLAME LENGTH

NOTE: PILOT SHIELD REMOVED FORCLARITY SPARK GAP 2 to 4mm

6.5 Testing - Gas

With the boiler on proceed as follows:-Test for gas soundness around the boiler gas componentsusing a suitable leak detection fluid, in accordance with the current issue of BS6891.Check the main burner gas pressure at least 10 minutes afterthe boiler has lit, refer to Data Label.If necessary adjust the gas pressure to obtain the requiredsetting turning screw clockwise, to decrease pressure, see diagram 6.2. 23
221656D