how can i make my hot taps work?

Becky,
What do you mean by "don't work". Does any water come out of the tap at all or do you mean water comes out but it is not hot? If there is no water at all there must be a valve turned off somewhere, look under the sink. If you have just cold or luke warm water you probably have an instantaneous gas water heater. This may just take time for the hot water to get from the boiler to the tap, try leaving it on a bit longer. Also experiment with different water flow rates, these type of heaters won't heat much if the tap is turned on too much. If you get hot water upsatairs there can't be much wrong with your boiler.
Hope this helps.

Andy Hill
March 2008