Hi Mike, had the exact same problem in the Highlands!! Cured it by removing the flow reduction grommets (very clean water) and flushing out the system. Probably some strands of peat which sometimes comes off the mountain. Good luck. Can you do me a favour please? If you have a copy of the instructions or know where to get a copy, can you please get back to me. The programmes are complex and without the book of rules, I'm at a loss to use the machine to its full advantage. Thanks; Glyn M-D
Glyn Morgan-Davies
January 2006