Ravenheat error code 01?

Hello, My ravenheat boiler is coming up with 01 on the display and when this code comes up, no hot water or heating until i push the reset button. This happens after i have been using the hot water, it makes a shuddering noise then a click giving me the 01 code. the code means the following according to the manual. FAILED IGNITION SEQUENCE
- Check condensate drain is not blocked (where would this be?)
- Check gas valve operation (any ideas?)
- Check the fan starts (if it does not start what can i do?)
- Check Ignition control board and cables (check for what exactly? A loose wire? what do i need to check on the control board??)

Thanks in advance for your time and help.