Business Update

Safety of decorative gas fires - interpretation of clause 3.7.2 of AS 4558

For decorative gas fires one important feature is the prevention of the ignition of unburned gas. The relevant requirement in AS 4558: 2000 Decorative gas log and other fuel effect appliances is clause 3.7.2 which states:

When the pilot flame is turned down to the point where it will just actuate the flame safeguard system, the main burner, operating at any rate at which its control will permit, shall light safely and reliably from that pilot flame.

Energy Safety’s position is that, in general, testing to this clause has to involve progressive reduction of the pressure at the inlet of the controller to a point where the pilot flame just actuates the control valve. Satisfactory ignition performance has to be exhibited throughout this range.

Equipment for this testing includes ‘an adjustable regulator of adequate capacity’. This needs to be capable of fine adjustment to enable testing to be carried out at the point at which the control valve just actuates.

Any design of appliance that uses AS 4558 or a similar standard therefore needs to ensure that this central aspect of clause 3.7.2 is met.

While the point of actuation can be characterised by a particular appliance inlet pressure, this is likely to be specific to individual appliances. It is not appropriate to select and apply such data to other appliances even though they may appear identical.