If your pilot light was lit all along continue on this page if you just lit it click here.
At this point you should have all of your thermostats up as high as they will go and your pilot light is lit, and your boiler is cold.
check to see if you have power to the boiler, check to see if the circuit breaker is tripped and that all service switches are on,
make sure the gas control valve is in the on position and not the pilot position.
If your breaker is tripped, turn it back on, if it trips again as soon as you reset it one of your circulator pumps may be fried, remove power from pump put wire nuts on wires then try breaker again if it still trips call an electrician.
If the breaker stays on see if the boiler starts to run normally, if so you are done, but you need to wonder what caused the breaker to trip in the first place. the problem may come back, if it does you may need an electrician to check out the breaker or for some type of short, or one of your circulator pumps is pulling too many amps and will need to be replaced. If the breaker is not tripped and all of the switches are in the on position and the boiler is still cold, you need to use an electric meter to see if you have power to your main control box on the boiler. A very important note: if you see water dripping on to any electric box, DO NOT reset the breaker, get the leak fixed and call an election. Water and electricity do not mix.
Test the L1 and L2 terminals to see if you have 120 AC volts If you do not a switch is off, the breaker is off or a fuse is blown. double check all and if you still do not have power at L1 and L2 Call an electrician.
Note: not all controls will look like the one to the left This one has all of the high voltage (120 AC volts) covered in electric boxes, the boxes will need to be opened to test for power, there will be no L1 or L2 terminals you will need to remove wire nuts and test the wires. This is very dangerous, you can be hurt or accidently connect wires back the wrong way, please call a pro and do not attempt this yourself.
Lets do this together use the 24/7 Help Line.