****ing boiler system...

[Cozzer]

First appologies for yet another probably completly daft suggestion, but there is I suppose, no chance that your stopcock, under the sink could have been fitted backwards?
Steve

Well, you say that, but......

It is relatively new. The original was impossible to turn, and although it's in a nigh-on impossible to get to location, the plumber managed to replace it a couple of years ago. How he managed to do it, I honestly don't know! On his knees, having to lean into and through the back of a cupboard, can't have been easy for someone standing 6'8" tall!

So no, it's correct. Turn clockwise - the merest amount - and the water's off.

But thanks for the lateral thinking, Stevekane!

 

[Stevekane]

You probably know this already but traditional stopcocks have a difection of flow with often an arrow cast into the body to show which way, if fitted the wrong way round they can cause all manner of issue's,,but they still turn clockwise to turn off,,
Steve.

 

[Cozzer]

You probably know this already but traditional stopcocks have a difection of flow with often an arrow cast into the body to show which way, if fitted the wrong way round they can cause all manner of issue's,,but they still turn clockwise to turn off,,
Steve.

Wasn't aware, so thanks!
I'll strap on the ol' knee pads, shuffle as best I can through the cupboard, and have a gander.
Then I'll swear, back out, and next time remember my torch!

 

[Bingy man]

Well, you say that, but......

It is relatively new. The original was impossible to turn, and although it's in a nigh-on impossible to get to location, the plumber managed to replace it a couple of years ago. How he managed to do it, I honestly don't know! On his knees, having to lean into and through the back of a cupboard, can't have been easy for someone standing 6'8" tall!

So no, it's correct. Turn clockwise - the merest amount - and the water's off.

But thanks for the lateral thinking, Stevekane!

But it usually takes several turns to completely shut the water off and the same amount of course to open it . That said I’ve come across this but only when the mains pressure is extremely high and the stop tap is used as a reducing valve . So as above it could be fitted with the water flow going against the direction of the stop tap or the valve itself could be faulty or restricted. Had one once when the nut ghat holds the stop taps washer in place had come adrift and wedged in the outlet ..

 

[Cozzer]

But it usually takes several turns to completely shut the water off and the same amount of course to open it . That said I’ve come across this but only when the mains pressure is extremely high and the stop tap is used as a reducing valve . So as above it could be fitted with the water flow going against the direction of the stop tap or the valve itself could be faulty or restricted. Had one once when the nut ghat holds the stop taps washer in place had come adrift and wedged in the outlet ..

Hmmmm...who knows. I'm not a plumber.
All I know is what I've written before - at 5 mins past the hour, the water's off. At 12 o'clock, it's virtually a dribble. At only 5 mins to the hour, it blows your socks off, rattling pipes like you wouldn't believe, and forcing the neighbours to "comment"!
Forget turning the tap a full 360 or more! This is maybe 10 degrees, from totally off to armageddon!

 

[Richard_C]

Have you asked neighbours if they have fluctuating or very high water pressure?

I wonder if you are in an area with high pressure mains the water company stopcock, meter or whatever is faulty. After all, a fault in your stopcock could reduce pressure and flow but it can't create pressure that isn't there.

OFWAT has a page.

https://www.ofwat.gov.uk/households/supply-and-standards/water-pressure/

You should be able to get your local water company to check your pressure for free.

 

[woodbutcher2]

How about opening your stop tap almost all the way?

 

[Richard_C]

I'll strap on the ol' knee pads, shuffle as best I can through the cupboard, and have a gander.
Then I'll swear, back out, and next time remember my torch!

Now we've gone all modern I often just reach in with a mobile phone and take a few pictures at arms length. If you have the always on light enabled and take a few shots you usually get one or two that are helpful.

(my phone will take a picture if you set audio control to 'on' and just shout at it so no need to get a finger onto the take button)

 

[Cozzer]

Now we've gone all modern I often just reach in with a mobile phone and take a few pictures at arms length. If you have the always on light enabled and take a few shots you usually get one or two that are helpful.

(my phone will take a picture if you set audio control to 'on' and just shout at it so no need to get a finger onto the take button)

No phone, so....

Actually, that's a thought. Borrow my neighbour's (if he's in) ask about their pressure.

 

[Bingy man]

Hmmmm...who knows. I'm not a plumber.
All I know is what I've written before - at 5 mins past the hour, the water's off. At 12 o'clock, it's virtually a dribble. At only 5 mins to the hour, it blows your socks off, rattling pipes like you wouldn't believe, and forcing the neighbours to "comment"!
Forget turning the tap a full 360 or more! This is maybe 10 degrees, from totally off to armageddon!

I’m surprised your boiler hasn’t blown all the joints as many of the joints within your boiler rely on simple o rings to make the joint water tight . Excessive pressure can cause these joints to leak . So contact water company 1st and be prepared for a new stop tap if it’s found faulty .-where I live it’s 7 Trent and they don’t charge for anything their side of the stop tap . Do you have any plumbing cover with your house insurance or bank etc ,

 

[Cozzer]

How about opening your stop tap almost all the way?

Would you?!
Don't fancy trying it, if a mere 10 degrees can cause so much trouble!
God knows what would happen.
How many revolutions would you expect, fully open to fully closed?
3? 4?
4 x 360? No ta!

 

[Cozzer]

No phone, so....

Actually, that's a thought. Borrow my neighbour's (if he's in) ask about their pressure.

The beast, corner cupboard with a hole in the back, next to the kitchen sink.
Could it be in a more awkward position? Probably not, but anyway, here's the best shot I can get with a borrowed phone....

As I said, 3 mins-or-so to the hour. Turn an "inch" to the right - circa 5 past - water off.

 

[Richard_C]

Looks conventional enough so that points to the incoming pressure being very high.

Derbyshire, so chances are it is Severn Trent. Here is their page:

https://www.stwater.co.uk/help-and-contact/legal/customer-guide-to-our-water-pressure-policy/

They do say that a pressure reducing valve is something the customer has to install, but the OFWAT guidance suggests its up to the water company to ensure that pressure is safe:

Water companies should make sure that high water pressure does not cause damage to a customer’s property if the customer’s fittings meet normal standards. If you have a problem with water pressure, speak to your water company first.

 

[Bingy man]

The beast, corner cupboard with a hole in the back, next to the kitchen sink.
Could it be in a more awkward position? Probably not, but anyway, here's the best shot I can get with a borrowed phone....
View attachment 176324

As I said, 3 mins-or-so to the hour. Turn an "inch" to the right - circa 5 past - water off.

That is old and most likely part of it is seized. I’d definitely have that changed but not until the incoming pressure is checked and the outside stop tap in the drive is confirmed as 1. In good working order and 2 . Only isolates your property ( in case of issues fitting new internal stop tap )

 

[Cozzer]

That is old and most likely part of it is seized. I’d definitely have that changed but not until the incoming pressure is checked and the outside stop tap in the drive is confirmed as 1. In good working order and 2 . Only isolates your property ( in case of issues fitting new internal stop tap )

Fitted less than 2 years ago, replacing the old seized one.

 

[starfish]

Fitted less than 2 years ago, replacing the old seized one.

Does not look 2 years old to me. Get the water pressure tested and I'd change this valve to a new one.

If you have a fill loop pressure gauge you should be able to get an idea from that but keep the valve to the heating closed

 

[Cozzer]

Looks conventional enough so that points to the incoming pressure being very high.

Derbyshire, so chances are it is Severn Trent. Here is their page:

https://www.stwater.co.uk/help-and-contact/legal/customer-guide-to-our-water-pressure-policy/

They do say that a pressure reducing valve is something the customer has to install, but the OFWAT guidance suggests its up to the water company to ensure that pressure is safe:

Water companies should make sure that high water pressure does not cause damage to a customer’s property if the customer’s fittings meet normal standards. If you have a problem with water pressure, speak to your water company first.

Yes, Severn Trent for clean, Yorkshire Water for waste.
Causes all sorts of fun when (say) a roadside leak is spotted and reported! You have to identify - with photo if possible! - the shape and size of the nearest/offending manhole before ST or YW will take any action...

 

[Agent_zed]

If you are only turning the stoptap a small amount and then getting rattling pipe, it would suggest to me that this is due to the valve not being fully open. If you look inside a stoptap you'll see as you turn it, it raises the valve like a little gate. This takes many turns. If it's only partially open then there is a whole load of turbulance which I would think is what is causing the rattling as the water rushes past the valve. Pressure drops can cause cavitation. If you open it fully there should little to no resistance as it is then a straight through pipe of the same diameter.

Water hammer/rattling is (to my knowledge) caused by something stopping the flow very quickly ie. an electronic valve on a washing machine, or a partially open valve vibrating and causing the flow to stop and start. This is most evident when a tap or ballcock is slowly closing and gets to a specific point where the valve resonates.



If it were me I'd turn an outside tap on full blast down a drain and then turn your stoptap on full. I bet it will go past the rattling stage and become quiet when in flow pressures into and out of the stoptap are equal. There is no reason for it to rattle if it is flowing in an unobstructed pipe.

Others - please correct me if I am wrong.

 

[Bingy man]

Fitted less than 2 years ago, replacing the old seized one.

I’d wager he’s just changed the spindle and left the body in place -old and new are rarely compatible, you can see the ptfe around the spindle joint . This could be part of the issues you’re having. The plumber may have used parts from an older non compatible valve , hence my comment that it looks old, the handle is too chunky for a modern stop tap and the wall looks untouched. He could have just eased and lubricated it and fitted a new washer .

 

[Bingy man]

If you are only turning the stoptap a small amount and then getting rattling pipe, it would suggest to me that this is due to the valve not being fully open. If you look inside a stoptap you'll see as you turn it, it raises the valve like a little gate. This takes many turns. If it's only partially open then there is a whole load of turbulance which I would think is what is causing the rattling as the water rushes past the valve. Pressure drops can cause cavitation. If you open it fully there should little to no resistance as it is then a straight through pipe of the same diameter.

Water hammer/rattling is (to my knowledge) caused by something stopping the flow very quickly ie. an electronic valve on a washing machine, or a partially open valve vibrating and causing the flow to stop and start. This is most evident when a tap or ballcock is slowly closing and gets to a specific point where the valve resonates.



If it were me I'd turn an outside tap on full blast down a drain and then turn your stoptap on full. I bet it will go past the rattling stage and become quiet when in flow pressures into and out of the stoptap are equal. There is no reason for it to rattle if it is flowing in an unobstructed pipe.

Others - please correct me if I am wrong

Close - water hammer usually caused by the jumper in older taps and ball valves is seized usually due to limescale- hence your reference to turning taps and ball valves getting to a certain point and reverberating- the jumper is not absorbing the pressure so it starts vibrating- think the op has a few issues that could be connected or separate but a systematic approach is required hence why best option is water company ( free) and they can confirm the technical side ( pressure or other known issues) then outside stop tap in working order and open fully depending on advice from water company then replace entire stop tap if only to illuminate it and finally address issues with boiler if any still exist- job done.