no hot water to shower

[doughie]

can anyone help! i have just had my gas cooker and sink moved from my kitchen to the dining room temporarily (while we have an extension)
now i cant get any hot water to my shower,also both the hot water taps need to be fully opened before the boiler kicks in and starts heating the water (worcester 24 cdi boiler).the flame in my gas oven doesn't seem to be acting normal either.when i open my shower fully the boiler doesn't fire up at all.
it sounds like maybe a pressure problem ,either gas or water but the water pressure seems normal ,could it be a problem on the boiler or maybe a partial blockage or air in the gas pipework?
the new route of the gas pipework is now alot shorter than previously.
any ideas would be much appreciated.

 

[AdamW]

First step (forgive me if you have tried this already): go to the meter and find the valve. It will have arrows on it to tell you which way to turn to open and which way to close. Check that it is in the open position.