Why a burner clicks and will not light

One burner, whole cooktop

The single most common misunderstanding about gas cooktops is this: the spark module does not fire one electrode at a time. It fires every electrode on the manifold together, on every ignition attempt.

So when you turn on the front left burner and the entire cooktop starts ticking, that is not a fault. That is normal. The module is sparking all of them and only the one with gas flowing lights.

The consequence follows directly. If one electrode is shorted to ground, every ignition attempt on every burner bleeds through that short. The spark energy goes to the easy path instead of jumping the intended gap. The result is a cooktop where nothing lights properly and the owner concludes the whole ignition system is dead.

It is usually one electrode and a clean.

Why electrodes short

The electrode sits at the edge of the burner, at the exact height where boil-overs land. Sugar syrup, salted pasta water, tomato sauce and spray cleaner all leave a residue on the ceramic insulator. That residue is conductive when it is damp and often stays conductive when it dries.

The spark then takes the surface path across the wet ceramic down to the burner body, instead of jumping the air gap to the burner cap. You can often see it if you darken the kitchen: the spark appears at the base of the ceramic rather than at the tip.

Three sub-cases, in order of frequency:

Dirty. Clean the ceramic and the tip with a dry abrasive pad, get it properly dry, and it works. No parts.

Cracked. A hairline crack in the ceramic does the same thing permanently, and no amount of cleaning fixes it. Ceramic cracks from thermal shock, usually from cold water hitting a hot burner. This is a new electrode.

Misplaced cap. After cleaning, burner caps go back on rotated or not seated. The gap between electrode and cap changes and the spark cannot bridge it. Free fix, and a surprisingly common call.

When it sparks but still does not light

Different problem. Gas is not arriving where the spark is.

Check the burner ports. On a burner used heavily for years, the ports around the ring block with carbon and food residue and the flame cannot travel round the ring from the ignition point. A port cleaning restores it.

Check the orifice against the gas supply. This comes up on ranges that have been converted between natural gas and propane by somebody who did the conversion partially. An LP orifice on natural gas will not carry enough gas; a natural gas orifice on LP over-fires and roars. Both cause ignition problems, and the second one is a safety matter.

Check the safety valve if the burner has one. Some ovens and some burners hold the valve closed until a flame is proven. If the sensing element has failed, gas never flows regardless of how good the spark is.

Outdoors, it is grounding

An outdoor grill breaks this pattern. Indoors, ignition faults are usually the electrode. Outdoors, they are usually the ground path.

The spark needs a clean return through the burner body to the chassis. Salt air and moisture corrode the mounting bracket, and the return path goes high-resistance without anything looking wrong. The module clicks, the electrode looks perfect, and no spark appears. Cleaning up the ground connection is a five minute fix that people replace modules to avoid.

Isolating the fault yourself

If you want to narrow it down before calling, do it with the gas off at the appliance. Darken the room, turn a burner to the ignite position and watch where the spark actually appears at each electrode. The one sparking to its own base rather than to the cap is your problem burner. Tell us which one when you book and we will bring the right part.