Expansion vessel

ahfat41

Expansion vessel cost replacement on Valiant  boiler protec24. What is a reasonable price I should expect to pay? Thanks

WIAWSNB

This is going to be a finger-in-the-air figure.
The EV is around £50. Most likely a Pressure Release Valve will be required too - say a £enner.
It looks to be easily accessed, so should be doable in an hour, I'd suggest?
So, what, around £200?

bjorn_toby_wilde

If this is the same boiler you’re referring to in your other posts there won’t be many original parts left. Are you sure it needs replacing? Have you had a proper gas safe plumber look at it yet?

WIAWSNB

Good point, btw. Sounds like a 'fixed price repair' task, or a fresh start with a new boiler.

ahfat41

Yes it’s the same boiler am referring, one suggested replacing it as it is 10 yrs old. Not much confident with the gas engineer I contacted he was going through with by WhatsApp as was busy. Hot water but no central heating he did suggest a new boiler. My son did contact the other person who WhatsApp him and one of the key was not turned on properly. As soon as he did that, the water pressure shoot up then went down again and central heating is working again. Later on got fault 22 had to re pressurised again. Working now but the black sweat seems to be sweating cannot find any leak on the pipes. He wants to come and fix it for £270 but am not having him back. Not easy getting reliable tradesmen I am going to subscribe to a boiler and heating insurance. Am not sure whether they will check boiler before insured. After spending over £600, am gutted if I have to spend more or new boiler. To recap the boiler was working fine except he needed a replacement thermostat. I wish I have left it alone as could still control central heating manually. Trying to help son have made it worse for him.

rob7475

If you're struggling to find a good engineer, it might be worth contacting the manufacturer and see how much they will charge for a fixed price repair. 

WIAWSNB

ahfat41 said:

Yes it’s the same boiler am referring, one suggested replacing it as it is 10 yrs old. Not much confident with the gas engineer I contacted he was going through with by WhatsApp as was busy. Hot water but no central heating he did suggest a new boiler. My son did contact the other person who WhatsApp him and one of the key was not turned on properly. As soon as he did that, the water pressure shoot up then went down again and central heating is working again. Later on got fault 22 had to re pressurised again. Working now but the black sweat seems to be sweating cannot find any leak on the pipes. He wants to come and fix it for £270 but am not having him back. Not easy getting reliable tradesmen I am going to subscribe to a boiler and heating insurance. Am not sure whether they will check boiler before insured. After spending over £600, am gutted if I have to spend more or new boiler. To recap the boiler was working fine except he needed a replacement thermostat. I wish I have left it alone as could still control central heating manually. Trying to help son have made it worse for him.

Oh dear, Ahfat. This just gets worse - bit in bold above.

It sounds as tho' the issue with the CH not working was that the boiler pressure wasn't high enough. Boilers are designed to shut off in such cases - it's a safety feature.

Your son then did as he was (poorly) instructed - he turned that black tap. This caused the water pressure to 'shoot up', which suggests this is a system filling/top-up tap. The problem is, you should only top it up to just over 1 bar pressure, and then stop. If this tap is left open for too long, then the system will keep on filling and the pressure will 'shoot up', until it hits around 3bar. 

At 3 bar, a safety pressure valve opens to dump the excess pressure (out a copper pipe on the outside wall of your home). So, the pressure would usually remain at 3bar - which is too high.

The problem is, once this pressure valve has been opened, it often does not seal shut again, so continues to allow the system to empty. You'll then see the pressure drop down again, which you seemingly have. 

Can you tell us: was that black tap fitted by any of your 'plumbers', or was it always there? 

Do you have the faulty PCB from before?

I think your options now are to either go for a 'Fixed Price Repair' by a reputable company, ideally Vaillant themselves, and hope they'll fix everything for the £300-odd it costs, or go for a new boiler; a straight swap for another Vaillant might be less than £2k.

In either event, see if the new guy will comment on what he finds, and if you can demonstrate any incompetence in the previous work, you can challenge the other cowboys for at least a partial refund - or you'll MoneyClaim them for the lot.