****ing boiler system...

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Cozzer

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Location
Derbyshire
I've groaned before about out F22 boiler error. A Vaillant Ecotec Pro. During the summer, when the heating's not used, we used to get the F22 error every 4 or 5 days.
The plumber suggested we had a leak in the system, although we never found one. Everything else seemed to be working OK, so he stuck with the leak theory..."keep your eyes open".
We did, and never spotted anything. No damp carpets, no bulging ceiling....nothing.

As we hit early winter, the central heating was turned on...and the F22s became more regular. We operate the heating by using the wall thermostat - we were told that Vaillant clocks on the boiler weren't that dependable, hence using the wall job...
We never got an F22 during the day when the heating was working - it was always overnight when the thermostat had been turned "off".
The next morning we'd top the tank up by the filling loop with the two valves, and you'd hear the boiler kick in.
As time's gone on, the F22s started being a little more frequent - every other day was bad enough, but about a month ago, it became literally a daily event.

We'd asked the plumber to do a boiler service last September, before the onset on cold weather...he turned up last Sunday. By now, we had other problems. In the bathroom, unless you flushed the toilet first, the hot water pipes would be trying to free themselves from inside the wall. The sink hot tap would cough, splutter, fart and spit water at you. The pipes banging was so loud, even our neighbours commented. Well, complained, really. Eventually the bathroom sink cold tap started in harmony. The noise was horrendous; even the sink pedestal vibrated. You were almost afraid to turn the taps on...

Anyway, laddo checked the boiler, ruling out other F22 causes. Conclusion was the same - there's a leak somewhere. It's a solid floor under the lounge, so the money's on the leak being under it. He'd brought some liquid "magic leak sealer" which he added to the system, and so far, it's worked. No F22 since last Sunday....
And so to the banging pipes...."the pressure's too much". I don't know about these things, but laddo commented that it "must be about 10 bar". Might have been a jokey/off/whatever type comment, but he's been a plumber for above 30 years, so knows more than I do.
Under the kitchen sink sits the stop tap. At about 5 past the hour, the water's completely off. On the hour, it's a mere trickle out of the taps, hot or cold. At 5 to the hour, the banging's back with a vengeance. We settle around the 2 minutes to the hour, and no banging/rattling. Heaven.

I say "heaven". You can't use two "water items" at the same time. Flush the toilet? You have to then wait until the cistern fills before you can wash your hands, and the tap has to be fully turned on to get any worthwhile flow. If you don't wait for the cistern to fill, you get a dribble from the tap...
The washing machine takes an eternity to fill. The shower? You have to move around under it to actually get wet.... There's no "force" whatsoever.
To wash the dishes in the kitchen sink, you turn the tap fully open and wait for 30 seconds plus before the water is hot enough. I used to virtually fill the sink to wash the pots - I don't now. It would literally take 5 minutes plus.

This can't be right. It's driving me mad.

Tell me please - is it worth me sticking my arm down the mains tap/stopcock (?) on the pavement outside the house? Is it "too open"? Too "closed"? What?!
 
Hi Cozzer. In your position in I would contact your Water Utility supplier for emergency attention to your house water supply. The conditions of banging pipes you mention could be due to air that has got into the supply to your property. There might be a water main issue affecting your property. Good luck.
 
As dizjasta said, fluctuating water flow sounds like a supply problem with air in the supply somewhere.

Your F22 problem 'could' have been related to air in your supply also as when you top the system up the air will pressurise the system, however once it circulates around it will be vented out as your boiler has an auto air vent. However you state that it works happily until it cools down which is not aligned with this hypothesis. My conclusion would be the issues are coincidental. Hopefully the leak sealant has solved one of them!
 
As dizjasta said, fluctuating water flow sounds like a supply problem with air in the supply somewhere.

Your F22 problem 'could' have been related to air in your supply also as when you top the system up the air will pressurise the system, however once it circulates around it will be vented out as your boiler has an auto air vent. However you state that it works happily until it cools down which is not aligned with this hypothesis. My conclusion would be the issues are coincidental. Hopefully the leak sealant has solved one of them!
Frequent pressure loss could be a faulty expansion vessel. Water is lost via the over pressure valve thing(brain can't find the right name right now..) when hot, then pressure drops when everything cools down.
 
The plumber suggested we had a leak in the system, although we never found one.
Sounds like you need a better plumber, if you get a plumber round then he should be pressure testing the system and finding any leaks not you, if you suspect a leak under the floor then add some dye to the pressure tester and eventually that should seep out somewhere. Better to fix a leak then try and seal it with snake oil !

And so to the banging pipes...."the pressure's too much". I don't know about these things, but laddo commented that it "must be about 10 bar". Might have been a jokey/off/whatever type comment, but he's been a plumber for above 30 years, so knows more than I do.
You cannot put in 10 bar, I assume you meant 1 bar otherwise the over pressure valve will release.

Has he checked the pressure in the expansion vessel ? The purpose of this item is to accomodate the excess water in the system due to expansion as the temperature is increased, if it is faulty then as the water temperature is raised, the water will expand and because it has nowhere to go the pressure rises until the over pressure valve opens and dumps the excess water to drop the pressure, when the system returns to ambient you find the pressure is now low so you top it up again and the cycle repeats.
 
Laddo tested everything - he was here for over 3 hours. There's no sign of a leak, hence suspecting that it's under the concrete floor lounge.
And yes, "10" bar was the expression he used. As I wrote, I didn't know whether it was simply a handy phrase or literal. From what you say, just an expression.
As regards changing plumbers, he was the one who installed the Vaillant boiler, 5/6 years ago, having looked after the aged forerunner when we bought the property. He had to fit thermostatic valves to the old radiators, and warned us that we'd the "wrong type" of showers for the new boiler. He was correct about that - one of 'em packed in not long after.
 
Frequent pressure loss could be a faulty expansion vessel. Water is lost via the over pressure valve thing(brain can't find the right name right now..) when hot, then pressure drops when everything cools down.
Checked it, apparently....
 
Yep, sounds like the problem I had a couple of weeks ago, new valve and it's right as rain.

As for the water pressure, I'd ring the water company and say there might be a leak......See what they do.
 
Your biggest issue seams to be the water pressure is fluctuating from almost nothing to above what most plumbing is designed for .the water mains pressure should be constant apart from peak times . Depending on where you live will depend on what you get . Don’t quote me but I’d expect 1.5 to 2 bar as most combi boilers and pressurised water storage systems work around 1.2 —1.5 bar . Toilets not filling or baths taking forever to fill is a supply issue. If your incoming stop tap is fully open and the plumber has checked the one in the road or drive then as above contact your water supply company. I’d suspect a leak outside if the pressure was constantly low but you wouldn’t then get excessive pressure. Are you on a shared supply or does each property where you live all have a stop tap in ghe drive or path on your property boundary . Talk to you neibours as it sounds like they will also have problems. If you have a garden tap ( bib tap ) you can buy a pressure gauge that will give you a good indication of what you pressure is ( simply connect it to the garden tap ) with no taps running or appliances running ( drawing water ) turn on the garden tap fully and read the dial . Anything above 1 bar is good but above 3 can cause problems and you would need a pressure regulator.
This one below is from Toolstation.
Take readings at multiple times and record. Show this to the water company when they visit. Good luck ..
 

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Sometimes the internal bladder/bag inside the pressure vessel leaks, eventuality fills up with water. So when pressure rises in the system, it has no where to go, causing banging pipes.
It's easy to check, just depress the air valve on the side of the vessel (it looks like a car tyre valve) if any water comes out then the bladder/bag Inside the pressure vessel has a burst, so a new vessel is needed.
If only air escapes its fine, just pump it up to its required pressure when system is clod, iirc pressure vessel pressure should be about 1 bar
 
I'm with Bingy man. You need to check what the pressure actually is. 10 bar is a ridiculous figure. Check it at various times. If it fluctuates significantly then you have a supply problem. In that case I would try and get some readings from your neighbours as well. If their supply shows the same then probably the mains, their plumbing might just not exhibit the problems you have. If their supply is stable then that suggests the problem is somewhere between the main and your property, hard to think what it would be, but probably down to you to fix. If it's just too high then get a regulator. And you don't have to regulate the whole system, depending on the layout you could just regulate the supply to the pipes that are causing the problem. Having said that banging does sound like air getting in, high pressure alone isn't going to do that.
I would have expected any decent plumber to have a pressure gauge, and to have measured it.
As to your "leak" time will tell, if the leak stop fixes it long term then it's not the expansion vessel or PRV, as it won't affect either. We had a similar problem years ago, persistent slow pressure loss, no apparent leak. Fixed using Fernox leak stopper. Only discovered the actual cause years later when we had to remove part of the suspended floor downstairs. There was a short section of pipe with a compression joint at either end spanning a joist, presumably a repair. One of the joints had dried up staining around it, and on the slab below it. So the relatively small volume of water had dripped straight onto the slab and soaked in, no visible sign above atall.
 
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I've groaned before about out F22 boiler error. A Vaillant Ecotec Pro. During the summer, when the heating's not used, we used to get the F22 error every 4 or 5 days.
The plumber suggested we had a leak in the system, although we never found one. Everything else seemed to be working OK, so he stuck with the leak theory..."keep your eyes open".
We did, and never spotted anything. No damp carpets, no bulging ceiling....nothing.

As we hit early winter, the central heating was turned on...and the F22s became more regular. We operate the heating by using the wall thermostat - we were told that Vaillant clocks on the boiler weren't that dependable, hence using the wall job...
We never got an F22 during the day when the heating was working - it was always overnight when the thermostat had been turned "off".
The next morning we'd top the tank up by the filling loop with the two valves, and you'd hear the boiler kick in.
As time's gone on, the F22s started being a little more frequent - every other day was bad enough, but about a month ago, it became literally a daily event.

We'd asked the plumber to do a boiler service last September, before the onset on cold weather...he turned up last Sunday. By now, we had other problems. In the bathroom, unless you flushed the toilet first, the hot water pipes would be trying to free themselves from inside the wall. The sink hot tap would cough, splutter, fart and spit water at you. The pipes banging was so loud, even our neighbours commented. Well, complained, really. Eventually the bathroom sink cold tap started in harmony. The noise was horrendous; even the sink pedestal vibrated. You were almost afraid to turn the taps on...

Anyway, laddo checked the boiler, ruling out other F22 causes. Conclusion was the same - there's a leak somewhere. It's a solid floor under the lounge, so the money's on the leak being under it. He'd brought some liquid "magic leak sealer" which he added to the system, and so far, it's worked. No F22 since last Sunday....
And so to the banging pipes...."the pressure's too much". I don't know about these things, but laddo commented that it "must be about 10 bar". Might have been a jokey/off/whatever type comment, but he's been a plumber for above 30 years, so knows more than I do.
Under the kitchen sink sits the stop tap. At about 5 past the hour, the water's completely off. On the hour, it's a mere trickle out of the taps, hot or cold. At 5 to the hour, the banging's back with a vengeance. We settle around the 2 minutes to the hour, and no banging/rattling. Heaven.

I say "heaven". You can't use two "water items" at the same time. Flush the toilet? You have to then wait until the cistern fills before you can wash your hands, and the tap has to be fully turned on to get any worthwhile flow. If you don't wait for the cistern to fill, you get a dribble from the tap...
The washing machine takes an eternity to fill. The shower? You have to move around under it to actually get wet.... There's no "force" whatsoever.
To wash the dishes in the kitchen sink, you turn the tap fully open and wait for 30 seconds plus before the water is hot enough. I used to virtually fill the sink to wash the pots - I don't now. It would literally take 5 minutes plus.

This can't be right. It's driving me mad.

Tell me please - is it worth me sticking my arm down the mains tap/stopcock (?) on the pavement outside the house? Is it "too open"? Too "closed"? What?!
Sounds like a faulty/failing diverter valve inside the boiler system. Stop using local plumber for this unless he's Vaillant trained. Go direct to Vaillant for a list of trained engineers and you could be fixed within a few days.
Diverter valves are prone to failing on many combi boilers (assuming yours is such).
 
What does the Vaillant F22 error code stand for? An F22 fault happens when there's too little water pressure for your boiler to fire up. That's why, if you're looking at a Vaillant F22 fault code, your boiler is probably 'locked out', and there's no hot water coming from your taps or shower.

The Vaillant F. 22 error code is a sign that your boiler has low water pressure. To rectify the problem and to get your boiler functioning normally again, you'll need to increase the water pressure back to the right level. Vaillant boilers can only work when they have the right water pressure

 
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