How to replace unvented expansion vessel without draining cylinder (airlock it) subscribe

[@freezefoot]

Thank you .Learner Question please:@ 0:29 you said i pulled the T&PRV and made sure its closed.Do you mean you opened it momentarily(on the spring cap) to allow air in and then closed it(self closing) to make sure its fully sealing.Just need clarification.Never thought of this.New subscriber.Much appreciated.

[@plumbertime]

I pulled it until water stopped flowing from it. How ether I’m certain just running the hot tap until it stops then closing hot taps and not touching the tpr valve would still work. I was just extra cautious as never thought to try this way

[@freezefoot]

@@plumbertime Thank you for your reply👍

[@plumbertime]

@@freezefoot your welcome 👍 good luck

[@robinbrandon270]

Genius!

[@muppit666]

Why not put a drain cock and a lockshield valve whilst you’re there. Then next time you only have to isolate and drain the expansion vessel.

[@plumbertime]

You’re not supposed to fit a valve as then the expansion vessel could be isolated and not do it’s job.

[@muppit666]

@@plumbertime you can fit a lockshield valve and drain cock for servicing. You cannot fit an ordinary isolation valve. The valve must be tamper proof ie: you need tools to shut it. Some manufacturers even make such a valve complete with drain off built in for servicing pressure vessels.

[@plumbertime]

@@muppit666 thanks. I know they make these valves ect but as far as I’m aware they’re not to be fitted. If you can find a reg that says it’s ok to fit an isolation valve on expansion vessel send me it as it would be handy!

[@muppit666]

@@plumbertime I’ll have a look tomorrow and try and find the reg.

[@plumbertime]

@@muppit666 thanks I’d appreciate that. Read before you shouldn’t even fit gate valves on cold feeds apparently! Not sure if that’s being updated