The pilot burner should ignite the main burner quietly and reliably under all operating conditions, including low gas supply pressure. The ignition of the main burner gas should occur within 4 seconds from the time that gas is admitted to the main burner. This should occur when the pilot gas supply is reduced to an amount just above the point of pilot flame extinction.
A main burner ignition test should be performed after the main burner gas input and primary air adjustments have been made. The type of test used to check main burner ignition will depend on the type of pilot used in the gas-fired appliance. For example, in a pilot generator system, main burner ignition is checked with the pilot flame adjusted to the minimum millivoltage required to open the main valve. The manufacturer’ s installation literature for the appliance will probably include instructions for testing main burner ignition. If no literature is available, check with the local gas company.