Hi,

I am replacing my current 20 yr old HW cylinder and am considering
installing a mains pressure unvented system to remove the need for a
shower pump.

The installation instructions for some of these cylinders describe
particular building regulations to follow etc. and it does not look
overly complex but is the installation something that can be legally
carried out by a proficient diyer or does it require a professional.

Looking at the supplier web sites there seems to be quite a variation in
price between Thermasaver, Heatrae and Albion. Is there a significant
difference between them or does anyone have particular experience of
installing and commisioning them?

Thanks

Kevin