How to replace an expansion vessel.

[Vaskunito]

Hello guys,

could someone help me please. I need to replace this red expansion vessel that is leaking:

http://www.cs.ucl.ac.uk/staff/V.Zografos/pic2.jpg

so I decided to do it myself because the plumber who is servicing my building basically cannot be trusted and he always charges people double the price and never gives receipts.

I was wondering if someone could give me step by step detailed instructions on how to go about replacing it. Assume that I bought a new expansion vessel with similar specifications, and I have isolated the current vessel from the supply (i.e. no water is coming in) how do I go about installing a new one?

I assume that there is some considerable water/air pressure involved so it can be really a simple process of removing the old and installing the new yes?
Also, as you can see from the photo both the red and white expansion vessels have a little black valve (not so visible on the red in the photo). What exactly is this?

Anyway. I would appreaciate any help guys because I really dont want to result in calling the plumber.
Is it difficult to replace an expansion vessel?

Thank you very much in advance.
V.

 

[Paul Barker]

Send yourself on an unvented course first, write to council to let them know your plans and go ahead with it.

 

[chrishutt]

Switch off power to pump, isolate water supply to pump (same side as vessel to be replaced), open shower to release pressure, isolate downstream pipe from pump to shower if valve available, look for point to drain water from pipe - perhaps undo joint, unscrew old pressure vessel, screw in new vessel, open isolating valves, open shower to vent air, turn on power to pump, use shower.

Black knob on pressure vessel is air charging point - leave alone.

Paul, it's not an unvented cylinder, just a shower pump.

Actually, thinking about it, why not replace the whole pump assembly? It looks like it's done its duty and some.

 

[Vaskunito]

Hi guys and thanks for the replies.
Sounds quite straight forward.

By the way...if I were to call a plumber for this, how much do you think that it would cost? (including the price of a new vessel).

 

[Vaskunito]

Actually, thinking about it, why not replace the whole pump assembly? It
looks like it's done its duty and some.

Yes it was suggested to me before. Any idea of the costs for that? I ask because I dont trust my plumber

 

[chrishutt]

I dont trust my plumber

Who does? That's why I'm a plumber - couldn't trust anyone else.

 

[Vaskunito]

I dont trust my plumber

Who does? That's why I'm a plumber - couldn't trust anyone else.

Damn right
And after paying £200 for him to replace kitchen taps worth £50, and once when I had a problem with the pump in the photo (kept on going on at random) and he came, checked for 5 minutes, said "Sorry mate that's an electrical problem!!!" and I had to pay £60 for that... I said enough is enough. From then onwards I have been fixing any plumbing problems by myself.
But I am quite apprehensive about meddling with the expansion vessel.