Gas Fitter Practice Test

On a direct spark ignition control, what is the trial for ignition?

1. 10 seconds

2. 0.8 seconds

3. 4 seconds

4. 2 seconds

The correct answer is: 4 seconds

The correct choice is based on the standard practice for the operational procedure of direct spark ignition systems. A trial for ignition refers to the timeframe during which the ignition system attempts to light the burner after a call for heat is initiated. In many direct spark ignition systems, the ignition trial period is typically set to around four seconds. This duration allows sufficient time for the spark to ignite the gas and ensures proper combustion. If the ignition does not occur within this period, the system will typically shut down or proceed to a safety lockout to prevent the accumulation of unburned gas, which could pose a safety hazard. The choice of four seconds strikes a balance that allows for enough time to establish ignition while also protecting against prolonged attempts that could lead to dangerous situations. Shorter timeframes, like those suggested in other answer options, may not provide adequate opportunity for ignition, which is why they are less appropriate for direct spark ignition controls.