F22s again...

[Cozzer]

Yes, they're back.
Actually, for some weeks now. Every 2 days or so, boiler error F22. Just checking the wall calendar, this morning's was the 11th this month.
Still no sign of a leak anywhere, so suspicious that if it is a leak, it'll be under the only concrete floor we have. According to the plumber, everything else that could be causing the error checks out OK.
As reported before, our downstairs water stop tap is virtually off because of all the pipes banging and groaning. The downstairs shower room washbasin - handy to use if you've been gardening/whatever - has the novelty aspect that you've finished hand washing before any hot water emerges. Not so bad at this time of year, but a bit of a system shock over winter!
We're thinking of stripping it all out - boiler an' all - and starting afresh. Just need to count the pennies first.
Endorsements therefore please, for a good dependable boiler to replace the 6/7 year old Vaillant Eco job...ideally with something better than the 12 month Vaillant guarantee this time!
Ta muchly....

 

[bushwhaker]

The most common mistake they make. Here's what i found about them.
https://www.aspect.co.uk/blog/vaillant-boiler-f22-fault-code/

 

[Phill05]

Have a look at "Alpha boilers" Plumber advised these boilers are very good and long 15 year guarantee had one fitted early in the year after having a Glowworm that expired at 9 years old.

 

[Bingy man]

I’d not really be wanting to change a 6/7 year old vailiant tbh they are good boilers along with Worcester but you as said before need to illuminate the system side and that crazy sounding mains water pressure. Imagine your pain and hurt if you replace the boiler at considerable cost and after a week you wake up to f22 or the equivalent again . A pressure reducing valve or diaphragm will keep the cold mains to your boiler within its operational limits . This is a small low cost job … so you have an area of solid floor ??? This is what I found after multiple engineers had put leak sealer into the system of several years to cure a similar problem
After crawling under the suspended floors the only part that was solid had this little surprise a 25year old unsoldered joint . Job done and he was thinking of changing a 5 year old Worcester combi..

 

[J-G]

Hmmmm. . . I had an F22 error code a little while back and after two 'Professional' plumbers advised that I simply needed to replace the boiler, or at least have an expensive re-furb but failed to provide a firm quote after 3 prompts siteing lack of response by 'wholesaler'; I found a proper local man who suggested that it was most likely to be a 'Sensor'.

He took the existing one out in about 10 minutes confirming that it had indeed degraded. It took him 2 days to get a replacement and another 10 minutes to fit it. - Result - I think he charged me £45.

Regrettably I can't now recall exactly what he called the part but there can't be that many 'sensors' - and it was very obvious.

 

[RobinBHM]

Yes, they're back.
Actually, for some weeks now. Every 2 days or so, boiler error F22. Just checking the wall calendar, this morning's was the 11th this month.
Still no sign of a leak anywhere, so suspicious that if it is a leak, it'll be under the only concrete floor we have. According to the plumber, everything else that could be causing the error checks out OK.
As reported before, our downstairs water stop tap is virtually off because of all the pipes banging and groaning. The downstairs shower room washbasin - handy to use if you've been gardening/whatever - has the novelty aspect that you've finished hand washing before any hot water emerges. Not so bad at this time of year, but a bit of a system shock over winter!
We're thinking of stripping it all out - boiler an' all - and starting afresh. Just need to count the pennies first.
Endorsements therefore please, for a good dependable boiler to replace the 6/7 year old Vaillant Eco job...ideally with something better than the 12 month Vaillant guarantee this time!
Ta muchly....

Ask on DIYnot

It’s a forum with a hidden forum for gas engineers so the main forum itself has lots of heating engineers.

You will probably get professional advice on there.


Not sure if you have combi or system boiler, but if you decide tto update get weather compensation / hot water priority.

 

[Cozzer]

I’d not really be wanting to change a 6/7 year old vailiant tbh they are good boilers along with Worcester but you as said before need to illuminate the system side and that crazy sounding mains water pressure. Imagine your pain and hurt if you replace the boiler at considerable cost and after a week you wake up to f22 or the equivalent again . A pressure reducing valve or diaphragm will keep the cold mains to your boiler within its operational limits . This is a small low cost job … so you have an area of solid floor ??? This is what I found after multiple engineers had put leak sealer into the system of several years to cure a similar problem
After crawling under the suspended floors the only part that was solid had this little surprise a 25year old unsoldered joint . Job done and he was thinking of changing a 5 year old Worcester combi..

We/the plumber tried the leak sealer idea - it worked for a few weeks/months, but it was ironic that we still continued checking for errors every day, such was the habit/routine we'd adopted over the months!
I'm not sure about them being "good boilers"....both internal PCBs have had to be replaced, and they weren't cheap either.
Yes, the only concrete floor is under the biggest room, the lounge. The plumber's traced the piping from the cellar head, and where it re-emerges in the kitchen, but can't be certain of the routing under the lounge. As he says, if he "guesses wrong"....well, that was enough to put the frighteners on she who must be obeyed. We're too old for all the upset, so on the face of it, will end up adopting some stupid, eccentric, daily routine!

 

[Spectric]

Have you actually done a pressure test on the pipe work ? This is the only way to confirm that there is a leak and maybe get closer to where it is, you may have to disconnect pipework but guessing is a good way to spend lots of money and get nowhere. F22 is low pressure, either actual low pressure or a faulty pressure sensor so measure the pressure and get an actual value rather than rely on the boilers gage.

The plumber's traced the piping from the cellar head, and where it re-emerges in the kitchen,

So isolate the pipe work on both sides and pressure test it, if it fails to hold pressure you know the issue is under the floor. Now you coud attach a hose both sides and just flow water through and into a drain, with a listening rod like the water companies use

https://www.wardsflex.co.uk/wooden-cupped-5-listening-stick/

hunt for a leek under the floor and you might find it.

for a good dependable boiler to replace the 6/7 year old Vaillant Eco job

If you have space for a hot water cylinder then fit a system boiler and avoid combi's. A properly fitted Worcester boiler and something like an OSO cylinder will be more efficient but upset the heating engineer as he will get less work in future.

 

[Spectric]

I should have added that you could also loop out the boiler and pressurise to see if that holds pressure, this would ensure the excess pressure valve is not seeping or the expansion vessel.

 

[Old.bodger]

All good advice.
Before spending considerable money …just confirm that the following have been done:
Prove boiler pressure sensor, tricky, usually means a replacement so not top of the list!
Insert independent pressure gauge
Pressure test boiler heat exchanger
Test / check / weigh any expansion vessels
Replace any pressure relief valve….these are a nightmare and I consider them a standard candidate for replacement even if only triggered once.
Isolate and pressure test section under solid floor. I suggest leave pressurised for at least 24 hrs.

Otherwise WB offer a long warrantee provided you service the boiler every year. STRICTLY within 365 days….no exception or they will argue!


Just had a read through again. Get a pressure reducer fitted on the mains. Not expensive and good protection.

 

[Cozzer]

Well, as far as I know, all the "check items" mentioned above in various posts have been done....not by me, I hasten to add - I'll not go near it with a bargepole!
Whether it's all part and parcel, I don't know, but for the past few months we've had lots of water problems. I've mentioned all this before...for example, the stoptap in the kitchen....completely shut at 5 past the hour, way too powerful at 5 to... We have to settle with it at 12 o'clock, and the pathetic flow it gives.
In the last few weeks we've "lost" the upstairs shower, a St.James Brittania. No hot water. Replacement with thermostatic gizmo, from £650.
Unwilling to replace before the rest of the **** is sorted....

 

[Old.bodger]

You HAVE got to solve the mains pressure issue. Get a pressure reducer fitted. As you have experienced, partially closing the valve will give you dreadful flow. What is not so obvious is the when you are not running water the system pressure will still rise to the supply max. This can ruin your various ‘appliances’. You could take this up with your supplier, but to be honest, it will be easier to get your plumber to sort it. The part is sub £50.

 

[okeydokey]

I haven't reread the entire posts but for goodness sake get the stop **** replaced. If it's not easily accessible get one installed on the house side of the supply and then turn the old one 90% on and you now gave a working stop ****. If the speed/volume of water is too fast regulate or turn it down to about 80% on with newstop ****, if its bonkers fast get your water supplier to come and looksee as they may be delivering too high a pressure

 

[Spectric]

You HAVE got to solve the mains pressure issue. Get a pressure reducer fitted.

The supply pressure to the property is down to the water authority, if they say it is within limits then you have a big plumbing issue in that your system cannot handle normal mains pressure and fitting a pressure regulator in these circumstances is just hiding the real issue.

 

[Terry - Somerset]

Daughter had a similar problem and system needed topping up every few weeks. Eventually traced to a weeping bathroom radiator. Just an aside - what fluid loss is required from "normal" to F22 .

I can only think a minor leak will mostly evaporate rather than leaving obvious damp patches, particularly in winter when the heating is frequently on.

Boiler replacement, unless old and inefficient, is an expensive and possibly foolish solution.

 

[Bingy man]

I should have added that you could also loop out the boiler and pressurise to see if that holds pressure, this would ensure the excess pressure valve is not seeping or the expansion

Daughter had a similar problem and system needed topping up every few weeks. Eventually traced to a weeping bathroom radiator. Just an aside - what fluid loss is required from "normal" to F22 .

I can only think a minor leak will mostly evaporate rather than leaving obvious damp patches, particularly in winter when the heating is frequently on.

Boiler replacement, unless old and inefficient, is an expensive and possibly foolish solution.

These boilers can also leak internally via the heat exchanger and the water simply goes down the condense outlet into the waste pipe. Also the exp vessel you mention and of course the safety valve. That’s why so many combo,s get changed - the route cause is never identified - 1 abnormal mains water pressure 2 possible leak on system pipework 3 possible fault on chb 4 faulty filling loop causing excessive pressure in which case the safety valve will open to release pressure leaving the system pressure below 1bar hence f22 . The same will happen with a faulty , flat or leaking expansion vessel. Often miss diagnosed is the expansion vessel due to the small hose or capillary tube which connects it to the hydraulic block or pump manifold but this too will cause excessive pressure rise and can also force the safety valve to open and of course f22 .. edit I should also add that a combination of these core issues could be to blame . A systematic approach is reqd to illuminate these possibilities untill you end up with the actual cause or causes..

 

[Cozzer]

Daughter had a similar problem and system needed topping up every few weeks. Eventually traced to a weeping bathroom radiator. Just an aside - what fluid loss is required from "normal" to F22 .

I can only think a minor leak will mostly evaporate rather than leaving obvious damp patches, particularly in winter when the heating is frequently on.

Boiler replacement, unless old and inefficient, is an expensive and possibly foolish solution.

I asked the same question about fluid loss - the answer was "a mug full".
I take your point about finding damp patches, but there is absolutely no sign, even over summer when the CH isn't on. Bear in mind our F22 is currently every other day, that's a fair amount of liquid to not spot, if you see what I mean!
I'm the first to admit that I know less than nothing about boilers/water supply, so I tend to try and record whatever info I can in case it's helpful to the plumber laddo when he calls.
For instance, went to bed at 1am this morning....checked the boiler numbers, and it showed 0.9 pressure. No F22, although it was "due", the last being on Saturday.
Up at 6am, checked it again...1.3.
After washing etc., up to 1.6....
I don't pretend to know whether that range of numbers is "normal"...?
For that matter, how close 0.9 is to becoming an F22 error?

 

[Bingy man]

It varies from boiler to boiler and even different models from the same maker . Some will shut down at 0.5 bar ( lock out ) others will continue to run at 0 bar but usually with poor hot water temps. Then there are those that will flag up low pressure as a warning ( flashing light or code ) but continue to run .. but all the advice in the world, pictures, fault codes etc is no substitute for standing in front of your boiler and observing it in operation, viewing the system pipework and carrying out a few basic checks . Your excessive water pressure needs to be addressed because it’s unlikely that this would not affect your neighbours also . Combi,s operate at a max pressure as well as a minimum. What checks has your plumber done - also there is a big difference between a heating engineer and a plumber ( no disrespect to plumbers ) your water company is responsible for the pressure from the main to the stop tap on the service pipe supplying you property by government guidelines. So spending £1500-£2000 on a new boiler be it a quality boiler or a cheaper one is pointless untill you have all of the facts in front of you by qualified and experienced professionals ( imho)

 

[Bingy man]

I asked the same question about fluid loss - the answer was "a mug full".
I take your point about finding damp patches, but there is absolutely no sign, even over summer when the CH isn't on. Bear in mind our F22 is currently every other day, that's a fair amount of liquid to not spot, if you see what I mean!
I'm the first to admit that I know less than nothing about boilers/water supply, so I tend to try and record whatever info I can in case it's helpful to the plumber laddo when he calls.
For instance, went to bed at 1am this morning....checked the boiler numbers, and it showed 0.9 pressure. No F22, although it was "due", the last being on Saturday.
Up at 6am, checked it again...1.3.
After washing etc., up to 1.6....
I don't pretend to know whether that range of numbers is "normal"...?
For that matter, how close 0.9 is to becoming an F22 error?

I’ve just read your post again in particular the time you went to bed at 1am and your pressure was 0.9 1.3 then 1.6 . I assume your heating is off ?? And hot water not in use - this is telling me your filling loop or assembly is passing-mains water is entering the system via the filling loop or assembly. Depending on how sensitive your boilers safety valve is if the pressure exceeds 3 bar it will open and release the pressure to protect the boiler components ( o rings and seals etc ) when sufficient water has been removed via the safety valve discharge pipework your boiler will then naturally go to f22 . It could be that your excessive mains water pressure is forcing its way back into the boiler/ system via the filling loop. So now if you think logically the pressure is increasing all the time even when it’s not in use but when you do use the heating the heat causes the pressure to expand eg 1.5 to 2 bar + the increase from the filling loop passing will easily achieve 3 bar then it opens and the whole process starts again . The recent lack of f22,s could simply be that you are not using the heating as much if you are using it at all.

 

[Spectric]

this is telling me your filling loop or assembly is passing-mains water is entering the system via the filling loop or assembly.

Should not be left connected really when not in use. Take a picture of this filling loop, I tend to also fit an extra double check valve in the system .