I have a Worcester greenstar cdi 30 and it comes up with c6 error code. I've had the fan replaced twice, the last time was just before Christmas. I live in a 4 bed old house and the boiler is out in the garage. Any advice?
I'm reluctant to continue to fork out the new fan and call out charge again.

Hi, I've been through similar repeated woes over the last few years where I was continually chipping away at problems - I ended up getting breakdown cover and I've got to say the main advantage to me personally was the peace of mind! When I was on that case, I used this site: Heating Breakdown Cover which I found really handy when making my choices.