Gas Hob Keeps Clicking When Nothing Is On

What's happening?

A gas hob lights each burner with an electric spark. Pressing and turning a control makes a small spark generator click at the burner. When the clicking continues after the control is released, or starts on its own, the spark is being triggered when it should not be. The commonest cause is water: after cleaning or a boil-over, moisture sits between the igniter and the burner and lets the spark jump continuously. A burner cap that has not been put back in place, or a cap on the wrong burner, can do the same. A control switch that has stuck, or a spark module that has failed, keeps sending the pulse. This is different from a hob that clicks and will not light, which is a fault at the burner and has its own page. With the gas off at the control, the click itself is only a spark.

What usually causes it?

• Water or food residue on the igniter electrode after cleaning or a spill
• A burner cap or head out of position, or fitted on the wrong burner
• A control knob or switch stuck so the igniter is always triggered
• A damp hob after a boil-over or steam from a cooker hood
• A faulty spark module or igniter lead
• A worn microswitch under a control

Is it dangerous?

Low, if no burner is lit and there is no smell of gas. The click is a spark, and sparking near gas is a risk only if gas is escaping. If you smell gas, do not touch any switch: leave the property and call the National Gas Emergency Service on 0800 111 999 (0800 002 001 in Northern Ireland).

Can I fix it myself?

Switch off the electricity to the hob at the socket or the isolator, so the clicking stops. Check all the controls are in the off position and none is stuck down. Lift off the burner caps and heads, dry them and the igniter carefully with a cloth, and refit them in the right places. Leave it for several hours or overnight to dry out, then switch the power back on. Do not take the hob apart or touch gas connections.

When should you call a gas engineer?

Call a Gas Safe registered engineer, or the manufacturer's approved engineer, if it still clicks after it has dried, if one control will not release, or if you smell gas. Replacing a spark module or switch on a gas hob should be done by someone competent on gas appliances.

What will the gas engineer actually do?

• Check the control switches and microswitches for sticking
• Test the spark generator and replace a failed module
• Inspect and dry or replace igniter electrodes and leads
• Check burner caps and heads are the right parts, correctly seated
• Test every burner lights correctly and the flame is steady and blue
• Check gas tightness at the hob connections

Who fixes this

• Gas appliance repair
• Gas cooker and hob installation

Questions people ask

Sources & References

1. Bosch: gas hob keeps clicking
2. Zanussi: the ignition on my gas hob keeps sparking
3. AEG: the ignition on my gas hob keeps sparking
4. HSE: domestic gas safety, homeowner FAQs