Delayed Ignition
To ensure a smooth ignition, when the valve first opens after turning on the main burner, no more than four (4) seconds should expire before the burner has completely lit off. Although problems with delayed ignition are most likely to occur with propane (because it is heavier than air), it can still affect natural gas appliances.
There are many other factors which may contribute to delayed ignition in the fireplace:
· Log placement ? logs may be out of position causing problems with flame carry over from the rear of the burner to the front burner.
· Too much ember material. Embers may block the flow of fuel and affect the flame carry over.
· Ember material or lava rock placed on the rear of the burner.
· Orifice out of alignment with the burner or dirt in the orifice.
· Pilot flame too low ? clean or adjust pilot for larger flame.
· Pilot out of alignment with burner ? adjust pilot bracket or hood so that the pilot assembly is parallel to the burner and the pilot flame hits the thermal generators and burns over main burner.
Strong downdrafts on naturally vented fireplaces can blow fuel away from the pilot light. Also ensure there is a pilot shield installed on the pilot assembly because down drafting can also cause the pilot light to be blown off of the main burner, causing delayed ignition. Short cycling of propane fireplaces can cause ignition problems that mimic delayed ignition. Unburnt fuel pools at the bottom of the firebox after the burner cycles off and, if the fireplace is turned back on before the fuel dissipates, the pooled fuel will light off rather loudly.