Unvented cylinder expansion vessel recharge

Quick video with tips on how to re pressurise unvented cylinder expansion vessel, few tips along the way
#boiler #breakdown #repair #tips #tipsandtricks #howto #plumber #plumbing #gasengineer

[@supersood2]

A well explained video so that a diy person can do this confidently and safely. A side note, press the schrader valve pin first to check no water has passed the rubber diaphragm which would mean a new tank is needed.

[@snapgas9832]

Just a side note to this, just because you get a tiny bit of water out doesn’t mean the diaphragm has gone, it can just be condensation build up!
Little tip for you 👍

[@tellylgeorge]

Thanks for posting this video very useful. Just had my cylinder serviced and my plumber put bit too much pressure into the vessel causing a groaning noise every time I turned hot taps on. I took vessel down from 3 bar to 2.5 bar and that sorted it. I think you’re supposed to match pressure with that on the PRV which is 3 bar in my case so hope that’ll be ok for my system even though it’s bit lower. 🤞

[@Murph9000]

The tundish looks dodgy as well. Looks like 15mm in and out, should be 22mm out per building regs and cylinder manufacturer (or 28mm if it's a long run). Also doesn't have 300mm vertical pipe below the tundish. If one of the relief valves decides to let go with a lot of flow, it will likely overflow inside the loft space.
Edit: Or, if that's 22mm in and out, and a 22mm T&P valve, should be minimum 28mm out.

[@Antonio-pq4fb]

Thanks for the video. Do you have to completely drain the hot water tank?

[@Currahee13]

Hello. Thanks for the video. Would the water coming through the tundish before the fix be cold? We seem to have a steady stream of relatively cold water coming through ours. Could it still be the expansion vessel do you think? Cheers

[@snapgas9832]

Hi
Please get an unvented qualified engineer to attend

[@Currahee13]

@@snapgas9832 ok will do thanks