How can i fix my vokera excell 80sp?

If it has >never< given enough hot water for a bath then it may have not been properly commissioned. When there is hot water demand the gas valve is meant to open full crack to give maximum heat output. If this is not happening the hot water throughput will be poor. This is realy is a job for a corgi man who knows his way round the boiler. Other problems with microswitches, diaphragms, venturi etc develop with age and are never present on a brand new boiler.

c
October 2008