unvented

We have a unvented system that was installed about 18 months ago. Everything works fine except for the shower - it has always been weaker than I had wanted, and has got worse in the last year or so. The main problem is that the shower flow rate slows to a dribble over the course of 10 minutes...

Hi all 4 bed detached, two bathrooms and cloakroom, 16 rads, and 4 people including two young children. Out hot water demands are growing by the day and if it wasn't already awful for just the two of us, our 10 year old Ravenheat combi boiler is proving entirely insufficient for our water...

I am considering replacing my gravity fed system with this one or should I go with an unvented cylinder. http://www.glow-worm.co.uk/homeowner/products/energy-35-store-1474.en_gb.html Mains pressure around 10-12 ltrs/min @ 1.5 -1.7 bar in the kitchen tabs. Any thoughts or reviews?