Pilot stays on zones open up after thermostat calls for heat but boiler don't fire up what could it be.

Any ideas?

Txs.

Check for any manual reset safety switches that you might have on the boiler, check for any tripped breakers or blown fuses, make sure pilot is lit, Good luck, Mike

I have a weil mclain cg 25 spon model that the pilot won't start, when I turn the switch on the boiler starts but it won't spark the pilot and the gas valve doesn't open neither.
Please help. It is getting colder by the hour.