www.cheapcentralheating.co.uk How to top up a combi boiler or sealed system central heating boiler This is quite easy to do -please check your boiler instruction to see what pressure you need to top it up to. Please be very careful on turning the valve on and also when turning it off please make sure you have turn it off correctly because if not your boiler may be damaged. As always if you do not want to tackle this give me a call and i can come out and do it for you – click here to contact me or phone me on 07725 692699 / 01943 876999. powerflush powerflushing powerflushes power flushing power flush power flush magnaclean boiler buddy fernox tf1 plumbing and heating Now hopefully this should be very easy so we have put a video up for you to watch