A question often received by the Technical Support team is what to do if the flame goes out after the ignition switch is released. If you find this is the case, first of all please ensure the burner is the correct way round with the flat side pointing up and the cone pointing into the mixing chamber. The correct orientation is shown in the Fig. 1.
The Jenway PFP7 flame photometer has a safety feature that uses a thermocouple to detect if a flame is burning in the instrument. If the flame is extinguished, the thermocouple will detect the reduction in the temperature and will shut off the gas flow. Please ensure that you press the ignition switch for at least 20 seconds or until the FLM display is lit. If the flame does not stay alight after this time you may need to increase to fuel content of the flame by turning the fuel valve anti-clockwise one additional turn.
Another possible solution to this problem is an adjustment to the thermocouple assembly (Fig. 2). The thermocouple may just need moving closer to the flame so that it reaches the temperature where the solenoid is activated to keep the fuel flowing to the burner. However the thermocouple may need to be replaced if it is faulty. Instructions for replacement of this part are given in sections 9.1.2 and 9.1.3 of the operating manual if this is required.