Replacing expansion vessel

[purplehands]

Hi folks, I noticed a drip from my overflow so went to check the pressure and got sprayed with water from the schrader valve, guessing the diaphragm is knackered in the expansion vessel so have ordered a direct replacement. I was wondering if this can be done without a full system drain, I know the vessel would be very heavy so would probably drill some holes in it to drain, but not entirely sure how to isolate it.

Any tips greatly appreciated!

Cheers

 

[DP]

Close tap on cold water supply to cylinder, Run a hot tap to release pressure.
Open prv valve to reduce EV pressure to zero

Crack the capnut open a turn or two on the expansion vessel but not all the way
If no water comes out the capnut, undo completely and remove vessels. You will get wet. Do not drill the EV

You could Nick the horizontal pipe run under the EV and catch the dribbles/ discharge water from the vessel. When no more dribbles, cut the pipe and empty EV into a container to allow easy removal

Ensure new vessel is one specified for hot water cylinder and not for heating

 

[gas112]

doesnt look like that vessel has and support make sure you buy a support for it something like this

Flomasta Expansion Vessel Fixing Kit - Screwfix

Order online at Screwfix.com. Universal wall-mounting kit for expansion vessels with a capacity of up to 25 litres. Includes wall-mounting bracket and adjustable mounting clip. FREE next day delivery available, free collection in 1 minute.

www.screwfix.com

 

[dilalio]

When putting new one in.
Put a tesla service valve on for future recharging without full drain down.

BES.co.uk | Next Day Delivery On 15,000 + Plumbing Supplies

Order Expansion Vessel Service Valve and other valves online at BES.co.uk. Low Prices, Free Next Day Delivery Available, 15k Plus Products in stock. P/N: 26402.

www.bes.co.uk

 

[Madrab]

Can I recommend that as it's an unvented cylinder and therefore a regulated appliance, for the safety of you and yours and to have the system setup correctly (correct pre-charge etc), I would recommend the work be performed by a qualified unvented engineer.

 

[purplehands]

A local plumber quoted £70 to replace so I’m just going ahead with that, for the sake of £70 it’s not worth the hassle to me, got to pick your battles!

 

[Madrab]

A local plumber quoted £70 to replace so I’m just going ahead with that, for the sake of £70 it’s not worth the hassle to me, got to pick your battles!

Just ask him to confirm he's qualified

 

[purplehands]

Aye he’s a fully qualified heating engineer, cheers

 

[dilalio]

Aye he’s a fully qualified heating engineer, cheers

With G3 ticket?

 

[MeldrewsMate]

Aye he’s a fully qualified......

Often wondered what that means.