Panic over - took the spout apart and found a piece of soggy cardboard in the spout end causing the block. It's easy when you know how!
Thanks for the reply.
Jeff
Hi guys,
I have installed a brand new Century bath mixer tap with shower hose in a brand new bathroom installation running off a combi boiler (1.5 bar pressure).
Initially all was well but after a day of service the spout does not allow water from the hot and cold to flow (only dribbles), BUT...