A very quick google seacrh for "combi logic 24 L2" gave me:
http://www.bristol.gov.uk/sites/default/files/documents/housing/council_housing/housing_repairs/Ideal%20Logic%20Combi%20Boiler.pdf
Search for "L2" in that document (use the search facility in your PDF viewer). It could be a blocked condensate pipe (Not frozen, not in this weather, but possibly blocked somehow)
Also: http://www.ukplumbersforums.co.uk/gas-safe-register-forum-public-forum/47312-logic-combi-30-l2-fault-code.html
Then go and learn how to use Google :-)
Gucking Foolgle it, July 2014
