I have a Carrier gas furance with a pilot that lights by an intermittent electric ignitor. Occasionally, when the thermostat calls for heat, the electric ignition will spark repeatedly but ultimately, the pilot will not light. If I turn the thermostat off and then back on again, the problem usually resolves, but often recurs with next cycle. Can someone please explain what probable causes there are and possible solutions? Is this something better resolved by a professional? Thanks for your help.

I'm just guessing here but if it is a 3 wire pilot it may be dirty and the gas is not reaching the burner tip properly.

It may be that the spark is happening at the wrong place ,away from the gas.

Seasonal inspections by a professional are always a good idea and sometimes offered at a discounted amount.