F22s again...

[Bingy man]

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 .

Trouble is it’s not easy for many people including the elderly or short sighted to fit the key or hose etc and refill the system so many are left connected for this reason. Honest engineers don’t want to charge call outs for such minor things as topping up the system and if said person lives alone it’s likely this could be several times a year. Also I’ve seen several times where a new combi has been installed but in a new location eg moved due to a new kitchen or bathroom into the garage or loft but the original filling loop has been left connected. The early loops didn’t have single let alone double check valves . The last post clearly says the pressure was 0.9 when he went to bed but had risen to 1.6 when he woke up - obviously a leak on the boiler or system would reduce the pressure not increase it. Could he have a leak on the system or boiler and a passing filling loop -rare but not an impossible scenario. I’ve seen this personally on gas installations where the system is losing 3 mbar but the emergency control valve is passing 3mbar so if the tightness test is not carried out correctly then this 3 mbar leak will not show up and you could potentially leave a gas leak .

 

[Cozzer]

Morning, boys....
In answer to recent questions, yes, the CH is (always) off overnight. The pressure numbers quoted - 0.9 and 1.3 - were indeed the last/first observed. After washing and a use of toilet flush it then rose to the 1.6 mark.
I'll take a photo of the (permanent) filling loop, but I'll have to borrow a phone to do so...that'll be later today, I suppose.


Edit : That was lucky - my neighbour's in all day, so I've got his phone for other snaps if need be.
What I refer to as the filling loop is the braided steel job...yes? Anyway, for what they're worth, here's the set up...

 

[Jester129]

Cozzer, completely as an aside, may I suggest you buy a cheap digital camera? They are marvellous things, and you will find that you can and will use one quite often, such as in this case, when you don't need to rely on neighbours to borrow their phone. Just sayin'.

 

[Agent_zed]

What I am not understanding in this scenario is that if the water pressure is really way over what it should be, all of the neighbours would most likely be experiencing the same problem! They will be on the same water main and, unless works have been done, will be on the same connections to the mains etc.

As already mentioned having the stoptap almost closed or full open will make no difference at all to the pressure. It will equalise when all the taps in the house are off. That is how pressure in a fluid works. It won't have less pressure in one part than another if there is even the smallest of openings to a higher pressure supply.

If you want less flow to your taps just fit non-full bore isolators, I think a 15mm version has a hole of about 10mm.

The only thing you are doing by having the stop tap mostly closed is reducing the flow. If your boiler needs a certain amount of flow then I would guess that is your problem. The banging when the stop tap is open is not due to pressure, it's the flow over a faulty valve/washer causing resonance when the valve is in a specific position.

Change the stop tap and I'd bet the problem will go away.

 

[Bingy man]

Morning, boys....
In answer to recent questions, yes, the CH is (always) off overnight. The pressure numbers quoted - 0.9 and 1.3 - were indeed the last/first observed. After washing and a use of toilet flush it then rose to the 1.6 mark.
I'll take a photo of the (permanent) filling loop, but I'll have to borrow a phone to do so...that'll be later today, I suppose.


Edit : That was lucky - my neighbour's in all day, so I've got his phone for other snaps if need be.
What I refer to as the filling loop is the braided steel job...yes? Anyway, for what they're worth, here's the set up...
View attachment 183736

Standard filling loop but difficult to zoom in on the nrv ( if fitted ) and assuming if it’s directional that the valves are in the correct orientation. As suggested by I think @Spectric they should be removed once the system is filled to the correct pressure. There should be 2 small chrome caps to seal the ends off to keep dirt out etc . They just need to be hand tight . With the heating off the pressure shouldn’t rise unless it’s being fed from another source - additional filling loop,, integral filling loop built into boiler that is passing or has been left partially open. The more of these points you can eliminate the closer you will get to the real problem ( s)

 

[Jasper42]

If the boiler has been checked ( could be the expansion chamber) with no issues then drop some sealer into the heating system. It will seal any minor weeps. Recommend to 3 people over the last few years and saved them some money.
https://www.screwfix.com/p/fernox-f4-central-heating-leak-sealer-500ml/766pp

 

[Cozzer]

If the boiler has been checked ( could be the expansion chamber) with no issues then drop some sealer into the heating system. It will seal any minor weeps. Recommend to 3 people over the last few years and saved them some money.
https://www.screwfix.com/p/fernox-f4-central-heating-leak-sealer-500ml/766pp

Done it, matey. Only lasts so long, as I've found out...

 

[Cozzer]

Bit dopey this morning...late night is my excuse....

Forgot the bathroom "routine", God forbid.
Ripped the front off the airing cupboard to check for F22. No...good. Would've been a surprise, because I topped up 24 hours ago. Then, the error on my part...
Washed hands first.....whoa! Forgot to flush the toilet first, whether needed or not! Enormous noise as a result, so tap off as quickly as poss, bolt to toilet and flush. Not a good way to come round first thing in a morning....
As the cistern is filling, turn hot tap on, wait 30 seconds for it to actually run warm/hot, sink plug in. Now conscious that the cistern is almost topped up, it's a scramble to add any cold water in the sink in case the water in the sink is now "too" hot. Turning the cold tap on "automatically" turns the still-running hot tap flow to a mere trickle.
Sufficient cold added, turn cold tap off, and the hot regains its flow.
Turn hot tap off, and breathe....

So this has become our morning routine. I say morning....any time of day actually. Forget one element, or "perform" in the wrong order, and you're in trouble.
I'm reminded when my now-late m-i-law began to lose it a bit - in her late 80s, to be fair - when she started asking me to change all the light bulbs on every visit because "they'd been in a while". I used to point out out that a new one could fail within minutes of me leaving, and the original outlast us both, but no....
2 lights in the kitchen....one 60w, and the other "had to be" 100w. Why? Because that's how it was when they moved in, 30 years before.


I know, I know......

 

[Spectric]

to add any cold water in the sink in case the water in the sink is now "too" hot. Turning the cold tap on "automatically" turns the still-running hot tap flow to a mere trickle.
Sufficient cold added, turn cold tap off, and the hot regains its flow.

That sounds like you flow is far to low for the boiler, anything less than about 10 litres per min is an issue. With a low flow it could also explain the very hot water. So your two issues both need fixing, the leak on the sealed side that results in F22 & low pressure and then the low flow because your stop cock is not open enough because of noise in the pipework.

 

[Bingy man]

Think I said from the outset of this thread that the incoming water main and excessive pressure issues need to be eliminated with a mains pressure test carried out to determine exactly what is being supplied. Stop tap should be more or less fully open so any doubt and change it . The op previously stated the pressure was rising with no demand ( heating) so unless he is taking seriously long showers or filling a hedge bath then the problem is water is entering the system and raising the pressure possibly enough to open the safety valve which will drop the pressure as that’s its function . F22 will follow . If the safety valve is continuously opening then the 3bar opening pressure could be compromised and these valves are known for passing ( leaking ) leak sealer is definitely not the answer.