Twangy tea

Just returned from our maiden trip in our brand new Elddis Avante 540. Once we were set up on site we put the kettle on, but unfortunatley could not drink it as it had a horrible twangy taste, Put this down to new water pipes etc and thought it would clear after a little use. Not the case, but then tried filling the kettle from the hot tap which was fine. My suspicions lead me to the carbon filter. I have looked on the Whale website and it quotes "to remove smells and bad tastes in water" Yes, well o,k, Any thoughts folks