no ignition?

Wor/Bos 350 combi, i switch the boiler on, circuit board switches (3 phase) click to start but the electronic ignition does not engage. the pumps are working, the fan is working but cannot ignite gas.it seems electrical but am unsure of next step. By coincidence I noticed a drip from the heat exchanger above circuit board. water may have dripped onto board. can I dry of with hairdryer.