Went to change a tap-washer on the hot bath tap for a friend - the hot
water is supplied from a combi - so shut-off the cold supply into the
boiler.

However, the water kept pouring out of the hot tap - left it running
for almost an hour - so pretty sure it wasn't coming from the boiler.

Ended up changing the washer with the water pouring out anyway - it
was a mixer angled at90 degrees - so the water just pumped into the
bath when the valve was removed,

Any idea why the water didn't stop when I cut off the mains supply to
the combi?

Thanks,
Mark.

On 29 Sep, 14:13, wrote:
Went to change a tap-washer on the hot bath tap for a friend - the hot
water is supplied from a combi - so shut-off the cold supply into the
boiler.

However, the water kept pouring out of the hot tap - left it running
for almost an hour - so pretty sure it wasn't coming from the boiler.

Ended up changing the washer with the water pouring out anyway - it
was a mixer angled at90 degrees - so the water just pumped into the
bath when the valve was removed,

Any idea why the water didn't stop when I cut off the mains supply to
the combi?

Thanks,
Mark.

It's plumbed into next-door neighbours ;-) ?
Thermostatic tap that actually had inputs for hot and cold ? Mind you,
there's usually protection the input such that if one of thm cuts out,
so does the other one - but such protection could only be on hot cut-
off ?
Now, if you also cut off water at the house stopcock and it still
worked ...
Simon.

In article
,
wrote:
Went to change a tap-washer on the hot bath tap for a friend - the hot
water is supplied from a combi - so shut-off the cold supply into the
boiler.

However, the water kept pouring out of the hot tap - left it running
for almost an hour - so pretty sure it wasn't coming from the boiler.

Ended up changing the washer with the water pouring out anyway - it
was a mixer angled at90 degrees - so the water just pumped into the
bath when the valve was removed,

Any idea why the water didn't stop when I cut off the mains supply to
the combi?

Either the shut off valve is bu****ed or you've not found the right one.
The latter easily checked - it should kill all the taps in the house.

By saying the one 'into the boiler' makes me think that's the one for the
central heating circuit.

--
*A backward poet writes inverse.*

Dave Plowman London SW
To e-mail, change noise into sound.

On 29 Sep, 15:45, "Dave Plowman (News)" wrote:
In article
,
* wrote:

Went to change a tap-washer on the hot bath tap for a friend - the hot
water is supplied from a combi - so shut-off the cold supply into the
boiler.
However, the water kept pouring out of the hot tap - left it running
for almost an hour - so pretty sure it wasn't coming from the boiler.
Ended up changing the washer with the water pouring out anyway - it
was a mixer angled at90 degrees - so the water just pumped into the
bath when the valve was removed,
Any idea why the water didn't stop when I cut off the mains supply to
the combi?

Either the shut off valve is bu****ed or you've not found the right one.
The latter easily checked - it should kill all the taps in the house.

By saying the one 'into the boiler' makes me think that's the one for the
central heating circuit.

--
*A backward poet writes inverse.*

* * Dave Plowman * * * * * * * * London SW
* * * * * * * * * To e-mail, change noise into sound.


Hi Dave,

The arrangement is that a 22mm pipe runs right into the combi - I am
assuming this is the incoming mains.
T'eed off this is is the filling loop which is connected to a 15mm
pipe into the combi.

I suspect that as you say, the shut-off valve may be broken.

Mark.

wrote:
On 29 Sep, 15:45, "Dave Plowman (News)" wrote:
In article
,
wrote:

Went to change a tap-washer on the hot bath tap for a friend - the
hot water is supplied from a combi - so shut-off the cold supply
into the boiler.
However, the water kept pouring out of the hot tap - left it running
for almost an hour - so pretty sure it wasn't coming from the
boiler. Ended up changing the washer with the water pouring out
anyway - it was a mixer angled at90 degrees - so the water just
pumped into the bath when the valve was removed,
Any idea why the water didn't stop when I cut off the mains supply
to the combi?

Either the shut off valve is bu****ed or you've not found the right
one. The latter easily checked - it should kill all the taps in the
house.

By saying the one 'into the boiler' makes me think that's the one
for the central heating circuit.

--
*A backward poet writes inverse.*

Dave Plowman London SW
To e-mail, change noise into sound.


Hi Dave,

The arrangement is that a 22mm pipe runs right into the combi - I am
assuming this is the incoming mains.
T'eed off this is is the filling loop which is connected to a 15mm
pipe into the combi.

I suspect that as you say, the shut-off valve may be broken.

Mark.

I think you will find the 22mm was the central heating pipe, and the 15mm
was the mains water input!

Toby...

In article ,
writes:
Hi Dave,
The arrangement is that a 22mm pipe runs right into the combi - I am
assuming this is the incoming mains.
T'eed off this is is the filling loop which is connected to a 15mm
pipe into the combi.

No, that 15mm pipe is the mains in.
The 22mm will be part of the heating circuit.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

wrote:

Went to change a tap-washer on the hot bath tap for a friend - the hot
water is supplied from a combi - so shut-off the cold supply into the
boiler.

Not a gate valve by any chance?


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

wrote:

The arrangement is that a 22mm pipe runs right into the combi - I am
assuming this is the incoming mains.
T'eed off this is is the filling loop which is connected to a 15mm
pipe into the combi.

Ah, that sounds like the return for the central heating... what is on
the other end of the filling loop? That is probably the mains. (The
boiler probably has a 15mm inlet for the mains water)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

In article
,
wrote:
Either the shut off valve is bu****ed or you've not found the right
one. The latter easily checked - it should kill all the taps in the
house.

By saying the one 'into the boiler' makes me think that's the one for
the central heating circuit.
x
Hi Dave,

The arrangement is that a 22mm pipe runs right into the combi - I am
assuming this is the incoming mains.

Unlikely - mains is usually 15mm.

T'eed off this is is the filling loop which is connected to a 15mm
pipe into the combi.

The other side of that 15mm would be connected to mains to fill it. But
should be disconnected after filling.

I suspect that as you say, the shut-off valve may be broken.

You need to find the main stopcock for the house mains water. Usually by
the front door or under the sink. Turning that off should stop the water
flow immediately. Check with the kitchen cold tap.

All this assumes it actually is a combi.

--
*White with a hint of M42*

Dave Plowman London SW
To e-mail, change noise into sound.

John Rumm wrote:
wrote:

Went to change a tap-washer on the hot bath tap for a friend - the
hot water is supplied from a combi - so shut-off the cold supply
into the boiler.

Not a gate valve by any chance?

Useless, poxy, spawn of satan ******* things!

Simple job turned into a mission yesterday due to one of these infernal
devices. "Hot tap in wash basin is loose". Quick look revealed a flexible,
and no back nut on the tap. Been like it since the lady moved in 2 years
ago apparently.

Shut off the gate valve on the HW tank feed, still dripped like they always
piggin do. Fitted a new back nut, re connected the flexible, opend up the
gate valve - nothing. Though it might be an airlock but no joy.

Cracked open the joint above the gate valve & got water, nothing when I
cracked the joint under it. Trip to Wickes for new valve.

Tank above only fed the HW tank, everything else mains fed, no way to drain
the tank. Used a rubber bung, lots of dust sheets & wet vac to change the
valve. Spindle corroded to buggery & had snapped off.

Stopcocks are as bad. Trying to turn the mains off for another job in the
same house, stopcock under sink wouldn't budge - and you just know that one
more attempt is going to make it leak. Outside stopcock 'pit' thoughtfully
filled with tarmac by helpful cable TV installer.

Plumbing badly needs to catch up with the 21st century IMO.



--
Dave - The Medway Handyman
www.medwayhandyman.co.uk

On 30 Sep, 00:26, "Dave Plowman (News)" wrote:
In article
,
* wrote:

Either the shut off valve is bu****ed or you've not found the right
one. The latter easily checked - it should kill all the taps in the
house.

By saying the one 'into the boiler' makes me think that's the one for
the central heating circuit.
x
Hi Dave,
The arrangement is that a 22mm pipe runs right into the combi - I am
assuming this is the incoming mains.

Unlikely - mains is usually 15mm.

T'eed off this is is the filling loop which is connected to a 15mm
pipe into the combi.

The other side of that 15mm would be connected to mains to fill it. But
should be disconnected after filling.

I suspect that as you say, the shut-off valve may be broken.

You need to find the main stopcock for the house mains water. Usually by
the front door or under the sink. Turning that off should stop the water
flow immediately. Check with the kitchen cold tap.

All this assumes it actually is a combi.

--
*White with a hint of M42*

* * Dave Plowman * * * * * * * * London SW
* * * * * * * * * To e-mail, change noise into sound.

Yep, deffo a combi.
The 22mm pipe is on one side of the loop and the 15mm is on the other
side.

I disconnected the end at the 22mm pipe, directed the loop at a bucket
and opened the valve on the 15mm pipe and mains pressure water
squirted into the bucket - with no change in pressure on the gauge of
the combi - so I am assuming this is the mains.

Due to a bit of over-filling we had to release some pressure from the
boiler - I though this could be achieved by disconnecting the 15mm end
and openinng the valve at the 22mm pipe - but nothing came out. I
ended up removing it from the bleed point on one of the radiators.

What is the normal way of releasing some pressure on a combi?

Thanks,
Mark.

In article
,
wrote:
You need to find the main stopcock for the house mains water. Usually
by the front door or under the sink. Turning that off should stop the
water flow immediately. Check with the kitchen cold tap.

All this assumes it actually is a combi.

Yep, deffo a combi.
The 22mm pipe is on one side of the loop and the 15mm is on the other
side.

That still doesn't make sense to me. Can you list all the pipes to the
boiler?

I disconnected the end at the 22mm pipe, directed the loop at a bucket
and opened the valve on the 15mm pipe and mains pressure water
squirted into the bucket - with no change in pressure on the gauge of
the combi - so I am assuming this is the mains.

Well yes. You fill the boiler heating circuit from the mains.

Due to a bit of over-filling we had to release some pressure from the
boiler - I though this could be achieved by disconnecting the 15mm end
and openinng the valve at the 22mm pipe - but nothing came out. I
ended up removing it from the bleed point on one of the radiators.

What is the normal way of releasing some pressure on a combi?

Either from the boiler drain/fill valve or any bleed valve in the system.
But that's not exclusive to a combi.

Thanks,

--
*I am a nobody, and nobody is perfect; therefore I am perfect*

Dave Plowman London SW
To e-mail, change noise into sound.

wrote in message
...
On 30 Sep, 00:26, "Dave Plowman (News)" wrote:
In article
,
wrote:

Either the shut off valve is bu****ed or you've not found the right
one. The latter easily checked - it should kill all the taps in the
house.

By saying the one 'into the boiler' makes me think that's the one for
the central heating circuit.
x
Hi Dave,
The arrangement is that a 22mm pipe runs right into the combi - I am
assuming this is the incoming mains.

Unlikely - mains is usually 15mm.

T'eed off this is is the filling loop which is connected to a 15mm
pipe into the combi.

The other side of that 15mm would be connected to mains to fill it. But
should be disconnected after filling.

I suspect that as you say, the shut-off valve may be broken.

You need to find the main stopcock for the house mains water. Usually by
the front door or under the sink. Turning that off should stop the water
flow immediately. Check with the kitchen cold tap.

All this assumes it actually is a combi.

--
*White with a hint of M42*

Dave Plowman London SW
To e-mail, change noise into sound.

Yep, deffo a combi.
The 22mm pipe is on one side of the loop and the 15mm is on the other
side.

I disconnected the end at the 22mm pipe, directed the loop at a bucket
and opened the valve on the 15mm pipe and mains pressure water
squirted into the bucket - with no change in pressure on the gauge of
the combi - so I am assuming this is the mains.

Due to a bit of over-filling we had to release some pressure from the
boiler - I though this could be achieved by disconnecting the 15mm end
and openinng the valve at the 22mm pipe - but nothing came out. I
ended up removing it from the bleed point on one of the radiators.

What is the normal way of releasing some pressure on a combi?

Filling loops have a check valve fitted, maybe its on the wrong pipe and it
wont allow you to release the pressure?
Opening either valve will normally get a flow of water, cold mains on one
and from the CH loop on the other.

On 30 Sep, 10:17, "Dave Plowman (News)" wrote:
In article
,
* wrote:

You need to find the main stopcock for the house mains water. Usually
by the front door or under the sink. Turning that off should stop the
water flow immediately. Check with the kitchen cold tap.

All this assumes it actually is a combi.
Yep, deffo a combi.
The 22mm pipe is on one side of the loop and the 15mm is on the other
side.

That still doesn't make sense to me. Can you list all the pipes to the
boiler?

I disconnected the end at the 22mm pipe, directed the loop at a bucket
and opened the valve on the 15mm pipe and mains pressure water
squirted into the bucket - with no change in pressure on the gauge of
the *combi - so I am assuming this is the mains.

Well yes. You fill the boiler heating circuit from the mains.

Due to a bit of over-filling we had to release some pressure from the
boiler - I though this could be achieved by disconnecting the 15mm end
and openinng the valve at the 22mm pipe - but nothing came out. I
ended up removing it from the bleed point on one of the radiators.
What is the normal way of releasing some pressure on a combi?

Either from the boiler drain/fill valve or any bleed valve in the system.
But that's not exclusive to a combi.

Thanks,

--
*I am a nobody, and nobody is perfect; therefore I am perfect*

* * Dave Plowman * * * * * * * * London SW
* * * * * * * * * To e-mail, change noise into sound.

Hi Dave,

I don't recall all the pipes - I'll try and take a pic later in the
week - because this is confusing me!
So if I disconnected the filling loop from the main-side and opened
the fill valve on the combi - would you normally expect water to come
out?
Or does it have some kind of check valve that allows water in, but not
out?

Mark.

In article
,
wrote:
I don't recall all the pipes - I'll try and take a pic later in the week
- because this is confusing me! So if I disconnected the filling loop
from the main-side and opened the fill valve on the combi - would you
normally expect water to come out? Or does it have some kind of check
valve that allows water in, but not out?

I'm not sure on your particular boiler. There should be a one way valve
somewhere in the filling loop to prevent contaminating the mains water.

--
*If your feet smell and your nose runs, you're built upside down.

Dave Plowman London SW
To e-mail, change noise into sound.

dennis@home wrote:


wrote in message
...
On 30 Sep, 00:26, "Dave Plowman (News)" wrote:
In article
,
wrote:

Either the shut off valve is bu****ed or you've not found the right
one. The latter easily checked - it should kill all the taps in the
house.

By saying the one 'into the boiler' makes me think that's the one
for
the central heating circuit.
x
Hi Dave,
The arrangement is that a 22mm pipe runs right into the combi - I am
assuming this is the incoming mains.

Unlikely - mains is usually 15mm.

T'eed off this is is the filling loop which is connected to a 15mm
pipe into the combi.

The other side of that 15mm would be connected to mains to fill it. But
should be disconnected after filling.

I suspect that as you say, the shut-off valve may be broken.

You need to find the main stopcock for the house mains water. Usually by
the front door or under the sink. Turning that off should stop the water
flow immediately. Check with the kitchen cold tap.

All this assumes it actually is a combi.

--
*White with a hint of M42*

Dave Plowman London SW
To e-mail, change noise into sound.

Yep, deffo a combi.
The 22mm pipe is on one side of the loop and the 15mm is on the other
side.

I disconnected the end at the 22mm pipe, directed the loop at a bucket
and opened the valve on the 15mm pipe and mains pressure water
squirted into the bucket - with no change in pressure on the gauge of
the combi - so I am assuming this is the mains.

Due to a bit of over-filling we had to release some pressure from the
boiler - I though this could be achieved by disconnecting the 15mm end
and openinng the valve at the 22mm pipe - but nothing came out. I
ended up removing it from the bleed point on one of the radiators.

What is the normal way of releasing some pressure on a combi?

Via a drain point. Bleeding the system if there is gas in it may be enough.

Filling loops have a check valve fitted, maybe its on the wrong pipe and
it wont allow you to release the pressure?
Opening either valve will normally get a flow of water, cold mains on
one and from the CH loop on the other.

The purpose of the check valve is to prevent any flow of water out of
the heating circuit (and potentially into the mains supply). Some check
valves have a bleed screw, but by no means all.

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

The Medway Handyman wrote:
John Rumm wrote:
wrote:

Went to change a tap-washer on the hot bath tap for a friend - the
hot water is supplied from a combi - so shut-off the cold supply
into the boiler.
Not a gate valve by any chance?

Useless, poxy, spawn of satan ******* things!

Can't say I have ever felt that charitable about them ;-)

Shut off the gate valve on the HW tank feed, still dripped like they always
piggin do. Fitted a new back nut, re connected the flexible, opend up the
gate valve - nothing. Though it might be an airlock but no joy.

Cracked open the joint above the gate valve & got water, nothing when I
cracked the joint under it. Trip to Wickes for new valve.

Yup, played that game before - why ain't the piggin thing working now -
all I did was xyz...

Tank above only fed the HW tank, everything else mains fed, no way to drain
the tank. Used a rubber bung, lots of dust sheets & wet vac to change the
valve. Spindle corroded to buggery & had snapped off.

Stopcocks are as bad. Trying to turn the mains off for another job in the

Not as bad a gate valves though...

same house, stopcock under sink wouldn't budge - and you just know that one
more attempt is going to make it leak. Outside stopcock 'pit' thoughtfully
filled with tarmac by helpful cable TV installer.

Plumbing badly needs to catch up with the 21st century IMO.

It has (possibly) but the answer seems to be plastic. Not sure what the
question was that prompted it though!

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Mon, 29 Sep 2008 08:22:22 -0700, mark.hannah wrote:

The arrangement is that a 22mm pipe runs right into the combi - I am
assuming this is the incoming mains.

Maybe wrong assumption: could be gas supply or either CH flow or return.

T'eed off this is is the filling loop which is connected to a 15mm
pipe into the combi.

Then the 22mm is likely to be the CH return (or possibly the flow) and the
15mm the cold main feed which is what you should have isolated.


--
John Stumbles

The clairvoyants' meeting has been cancelled due to unforseen circumstances.