Doubt it is to do with the new taps where did you turn the water off? If it was at the feed to the boiler try turning the stopcock a bit to restrict the water entering the boiler. Also unlikely to be trapped air as it will be mains pressure.
@Zebra_Cyclist started
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Doubt it is to do with the new taps where did you turn the water off? If it was at the feed to the boiler try turning the stopcock a bit to restrict the water entering the boiler. Also unlikely to be trapped air as it will be mains pressure.