gas safe register

Hi, I wonder if anyone can help with my conundrum. I had an electric, unvented hot water cylinder installed last year and the product was registered with the manufacturer. The installer had G3 qualification, which I've checked on Gas Safe register. Apparently though because the boiler is...

I have been trying to get hold of the building regulations compliance certificate of the boiler installer. I also have a problem in that the installation benchmark form has not been filled out. The boiler was installed from the previous house owner in 2014. After tracking down the installer they...