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

[DevsAd]

You can never say 100% that the gas pipe will not need upgrading. Sorry to give you bad news. But most Vaillant’s still have a 15mm gas connection.

I was very surprised to find my GlowWorm 30CXi had only a 15mm gas inlet. So it was 22mm all the way to within a few inches.

Actually - thinking about it now - it probably shouldn't have been a surprise as all the internal gas-carrying pipework in the boiler will be small dia, so having the inlet only 15mm ain't as weird as I first thought?

 

[Sarah Wykes]

The space under the boiler was enough to fit a microwave as this is how I hid the pipes, so at least 30cm high and then the depth of the microwave, so although the picture probably doesn't look like there's a lot of room, there was enough room for a microwave underneath the boiler - would this be enough room for an expansion vessel?

 

[DevsAd]

The space under the boiler was enough to fit a microwave as this is how I hid the pipes, so at least 30cm high and then the depth of the microwave, so although the picture probably doesn't look like there's a lot of room, there was enough room for a microwave underneath the boiler - would this be enough room for an expansion vessel?

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?

 

[Sarah Wykes]

There's a worktop then underneath space for a washing machine, so I am afraid no kitchen unit to go under. I will aim to get a photo again tonight, I may not be able to get back to the house until tomorrow though, whichever way I will get one and post it.

 

[Harvest Fields]

That external exp vessel doesn't have to be mounted next to the boiler, it can go anywhere on the rad pipe system. You might, for example, have a room where there's a unit close to a rad and it could be fitted in there? Not exactly pretty, but just looking for solutions.

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.

 

[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