Correct, fitting a type C is one way to fix the problem.about the lighting what type circuit breakers do you have running the lighting? as you should probably be using a type C ( not a general household type B ) as the start up currents from the lighting may cause it to trip ( i think thats right im in my 3rd year of electrics at college and thats what iv been told so i hope it helps )
I have fitted two type C breakers in my consumer unit.
1. One for hall and garage lighting circuit as when the hall bulb used to blow, which it used to quite often, being exposed to cold air, it tripped the type B breaker cutting the other hall light off and plunging the garage, where the consumer unit is into darkness. Not good. Fitting a type C fixed that, no trip on blown bulb. Later of course replaced with low energy bulbs and type B would not have been an issue.
2. When kitchen was extened, more downlighters were fitted (via transformers) and once or twice a week the type B would trip when lights were turned on. Fitting type C, lights always worked.
Technical type B, C & D here...