Told boiler needs a new expansion vessel along with pressure relief valve - how much should this be?

[sammathias]

Sorry if someone has already said but how has the bloke come to the conclusion you need a new vessel? Leaking water? Cant be recharged? Pressure always dropping?

 

[DevsAd]

It should be as close to the boiler as possible and on the return. It will not do the job properly if it is miles away from the boiler which is why it is built in to the boiler.

(Dare I?)

The reason it's built in to the boiler is because that's the obvious place to have it, rather than having to install a separate unit.

And, I guess it's not ideal, but I see no reason why it won't work anywhere on that return pipework - even 'miles' away (assuming we aren't literally talking miles but a different part of the house). The pressure rise - and fall - is gradual, and is evenly distributed throughout the pipe system.

 

[Harvest Fields]

(Dare I?)

The reason it's built in to the boiler is because that's the obvious place to have it, rather than having to install a separate unit.

And, I guess it's not ideal, but I see no reason why it won't work anywhere on that return pipework - even 'miles' away (assuming we aren't literally talking miles but a different part of the house). The pressure rise - and fall - is gradual, and is evenly distributed throughout the pipe system.

You can do whatever you want mate, but it should be situated on the return back to the boiler after all radiators/hot water(If system/open vent)/underfloor returns.

 

[DevsAd]

 

[jtsplumbing]

Just gone through your first post you mention the plumber who was doing a Gas Safety check is this a Rented property ? are you the tenant ? or the owner ?

 

[quality]

I've got the same boiler, and had the same problem. Wouldn't recommend taking a 15 year old boiler off the wall, especially as the flue may be damaged and you would need to pay for another.

If you can, fit an external vessel. 30 quid for the vessel from Toolstation, plus a bit of pipe and couple of fittings. Did mine myself. Before you go down this route, sometimes although the valve on old vessel is spurting water, the diaphragm can re-seat itself if you try inflating it with system drained. Not always though. You poss wouldn't need an espansion vessel as big as the one on my photo - I may have slightly over sized. Doesn't need to be above boiler either, could poss go underneath or other place - as long as it's plumbed into the heating return pipe near the boiler.

If the rest of the boiler is fine, I would definitely get it fixed. They are one of the best boiler's made and all parts are available and easy to fix. Prices reasonable too. Much better than modern Vaillant plastic rubbish.

View attachment 32809

I would recommend taking that 15 year old boiler of the wall and replacing it

 

[Martyn2]

Hi

We have a vaillant turbo max 824e rs combi boiler that has been serviced and we've been told that the boiler is found to be gas safe but is in need of a new expansion vessel along with a pressure relief valve.

How much should be expected to pay for this (Coventry)? I have only one quote from the guy who did the gas safety record. We were told that the boiler might need to be removed completely from the wall to have the new vessel fitted that the price could be significantly reduced if there was more headroom above the boiler so the old tank could be raised up from behind.

Sarah

As far as a new expansion vessel goes, there is an alternative. You can drain the system and after refilling, partially bleed one radiator, preferably in a room you don't use much. This will act as an expansion vessel. As the pressure relief valve is a purely mechanical device I suggest yo dismantle it, give it a good clean and retest.

 

[dan_the_plumber]

Had anyone actually considered reinflating the expansion vessel?

 

[ShaunCorbs]

As far as a new expansion vessel goes, there is an alternative. You can drain the system and after refilling, partially bleed one radiator, preferably in a room you don't use much. This will act as an expansion vessel. As the pressure relief valve is a purely mechanical device I suggest yo dismantle it, give it a good clean and retest.

you do realise the air will eventually move / get dispersed

 

[Martyn2]

you do realise the air will eventually move / get dispersed

I have been running my system like this for the past 4 years, no problem. Changing boiler this year though as the existing one is 15 years old.

 

[ShaunCorbs]

I have been running my system like this for the past 4 years, no problem. Changing boiler this year though as the existing one is 15 years old.

You sure your system isn't open vented?

 

[dan_the_plumber]

you do realise the air will eventually move / get dispersed

 

[dan_the_plumber]

you do realise the air will eventually move / get dispersed

 

[Martyn2]

You sure your system isn't open vented?

Positive!

 

[ShaunCorbs]

Positive!

That's a yes correct?

If so that's why you haven't had a problem

 

[Harvest Fields]

As far as a new expansion vessel goes, there is an alternative. You can drain the system and after refilling, partially bleed one radiator, preferably in a room you don't use much. This will act as an expansion vessel. As the pressure relief valve is a purely mechanical device I suggest yo dismantle it, give it a good clean and retest.

This used to be used as a short term fix to get people through the weekend on a Friday evening. Not a long term fix

 

[Sarah Wykes]

I'd have thought it pretty tight, tho' there's a chance (not sure of the size of vessel you need.)

What's under the microwave space - is there a kitchen base unit? If so, I'd have thought it could go in there.

Could you post a further-back picture to show what's around the boiler?

Sorry for the delay but here are some more pictures

 

[Sarah Wykes]

Sorry if someone has already said but how has the bloke come to the conclusion you need a new vessel? Leaking water? Cant be recharged? Pressure always dropping?

The pressure is always dropping

 

[Sarah Wykes]

Just gone through your first post you mention the plumber who was doing a Gas Safety check is this a Rented property ? are you the tenant ? or the owner ?

I am the owner, the first time renting the house and the tenant should be moving in in a couple of weeks

 

[sammathias]

The pressure is always dropping

Has he tried recharging the vessel? Renewed prv? Still dropping? Potential central heating pipework leak?

 

[DevsAd]

Assuming that the plumber has done the obvious stuff and checked that the boiler's exp vessel is knackered, then your options remain as before, Sarah.

1) New boiler - circa £2k
2) New boiler vessel + PRV - £350 (with the associated risk of disturbing the boiler, but looking at the photo the flue shouldn't be an issue).
3) Fit an external exp vessel and replace PRV - I dunno, £200-ish?

An external vessel could be fitted on that adjacent wall - very ugly indeed - or possibly in a nearby room (where do these pipes through the ceiling go to?)

Anyhoo, your own plumber is the guy who's going to carry out whichever of these jobs you decide on, so discuss the 3 options with him