I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I open the valve full, the noise goes, but turns up later at another rad. They generally only make a noise when the TRV's are closing as the room is warm, and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I turn the pump speed down, the noise abates somewhat, but the boiler starts kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what do I need to do to get rid of it?

Thanks!

On Tuesday, November 25, 2014 6:57:47 PM UTC, Tom Pickles wrote:
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I open the valve full, the noise goes, but turns up later at another rad. They generally only make a noise when the TRV's are closing as the room is warm, and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I turn the pump speed down, the noise abates somewhat, but the boiler starts kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what do I need to do to get rid of it?

Thanks!

I should have also stated that when I vent the rads, I never get any air out of them.

On Tue, 25 Nov 2014 10:57:45 -0800 (PST), Tom Pickles
wrote:

I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I open the valve full, the noise goes, but turns up later at another rad. They generally only make a noise when the TRV's are closing as the room is warm, and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I turn the pump speed down, the noise abates somewhat, but the boiler starts kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what do I need to do to get rid of it?

Thanks!

As you say the sound is not very good but my guess is that you have
one directional valves on the wrong end of the radiator.

But someone with a brain will probably be along in a mo.

On 25/11/2014 20:01, EricP wrote:
On Tue, 25 Nov 2014 10:57:45 -0800 (PST), Tom Pickles
wrote:

I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I open the valve full, the noise goes, but turns up later at another rad. They generally only make a noise when the TRV's are closing as the room is warm, and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I turn the pump speed down, the noise abates somewhat, but the boiler starts kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what do I need to do to get rid of it?

Thanks!

As you say the sound is not very good but my guess is that you have
one directional valves on the wrong end of the radiator.

But someone with a brain will probably be along in a mo.

One directional valves *normally* have an arrow on them somewhere, and
you can work out which way the flow goes by feeling each end of the
radiator when the system is first turned on.

On 25/11/2014 18:57, Tom Pickles wrote:
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it.
If I open the valve full, the noise goes, but turns up later at
another rad. They generally only make a noise when the TRV's are
closing as the room is warm, and it only affects upstairs rads.

Yup small bubbles through a nearly closed valve can make that sound.
Having said that, so could small particles of solid matter.

Has the system got enough inhibitor in it? (that will scavenge the
oxygen from the water, and slow the rate of corrosion which in turn
produces gas).

A particulate filter may also be a good idea. Such as a fernox TF1 or
similar. These catch particulates and magnetic sludge.

I have an open vented system, running off a Glow-worm micron 50FF. If
I turn the pump speed down, the noise abates somewhat, but the boiler
starts kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air,
what do I need to do to get rid of it?

An auto vent valve somewhere in the system near its high point might
also be good.

--
Cheers,

John.

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

I used to get a similar noise in one radiator. I used to expect to be able
bleed a lot of air out - but there never was any. Different boiler now -
TRV fitted and I don't hear it now. It used to sould like lumps of stuff
going through the valve!

In article 2,
DerbyBorn writes

I used to get a similar noise in one radiator. I used to expect to be able
bleed a lot of air out - but there never was any. Different boiler now -
TRV fitted and I don't hear it now. It used to sould like lumps of stuff
going through the valve!

It certainly sounded like bubbles to me but the o/p said no air on
bleeding.

It is an open system so low pressure and perhaps it's cavitation as flow
passes through the closing TRV orifice. In that case maybe throttling
the lockshield down a bit will reduce the pressure drop across the TRV
and perhaps reduce the cavitation.

I see from the video that the valve is supposedly bidirectional (double
ended right angled arrow) but it may have a preferred flow direction
which for that one I'd suggest is correct if that is the hot end of the
rad and that the pipework at the lockshield end is cooler (perhaps only
marginally).

--
fred
it's a ba-na-na . . . .

"Tom Pickles" wrote in message
...
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I
open the valve full, the noise goes, but turns up later at another rad. They
generally only make a noise when the TRV's are closing as the room is warm,
and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I turn
the pump speed down, the noise abates somewhat, but the boiler starts
kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what do
I need to do to get rid of it?

Thanks!

Cavitation is a possibility.
Steam/vapour bubbles appear and disapppear as pressure varies in different
parts of the system. (Usually at restrictions eg valves and pumps)
"Negative" pressure can appear so that the water boils at lower temperature.
The clue is that it is worse when the sytem is hot.

http://en.wikipedia.org/wiki/Cavitation

"Tom Pickles" wrote in message
...
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I
open the valve full, the noise goes, but turns up later at another rad. They
generally only make a noise when the TRV's are closing as the room is warm,
and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I turn
the pump speed down, the noise abates somewhat, but the boiler starts
kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what do
I need to do to get rid of it?

Thanks!

Reading your post again, cavitation seems quite likley.
The phenomenum occurrs when water pressure/head is too low.
You have an open vented sytem and it's worse upstair wher epressure is
lowest.

So the problem may be due to low head, your loft tank is not high enough
above the highest radiators or your pipework is on the small side meaning
the pump has to be turned up high so causing these pressure differences
leading to cavitation.

The cure is to move the tank higher or convert to pressurised system.
Sometimes moving the pump to the flow side of the boiler fixes the problem
but this depends to a degree on the boiler design/size of waterways.
In days of yore, the pump was one the return side of the boiler which
promotes cavitation but boilers had bigger waterways then and pipework was
bigger.

On Tuesday, November 25, 2014 10:45:03 PM UTC, John Rumm wrote:
On 25/11/2014 18:57, Tom Pickles wrote:
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)


Yup small bubbles through a nearly closed valve can make that sound.
Having said that, so could small particles of solid matter.

Has the system got enough inhibitor in it? (that will scavenge the
oxygen from the water, and slow the rate of corrosion which in turn
produces gas).

I did put plenty of Fernox inhibitor in when I last drained the system down and filled it.


A particulate filter may also be a good idea. Such as a fernox TF1 or
similar. These catch particulates and magnetic sludge.

I fitted a Spirotrap last year after I spent a weekend descaled the system using Fernox DS40 cleaner. I was having a lot of trouble with kettling in the boiler.

An auto vent valve somewhere in the system near its high point might
also be good.

Would an auto-venting rad bleed valve suffice, or should I fit something more like this?: http://www.screwfix.com/p/bottle-air-vent-15mm/34359

Thanks

On Wednesday, November 26, 2014 8:19:50 AM UTC, harry wrote:
"Tom Pickles" wrote in message
...
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I
open the valve full, the noise goes, but turns up later at another rad. They
generally only make a noise when the TRV's are closing as the room is warm,
and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I turn
the pump speed down, the noise abates somewhat, but the boiler starts
kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what do
I need to do to get rid of it?

Thanks!

Reading your post again, cavitation seems quite likley.
The phenomenum occurrs when water pressure/head is too low.
You have an open vented sytem and it's worse upstair wher epressure is
lowest.

So the problem may be due to low head, your loft tank is not high enough
above the highest radiators or your pipework is on the small side meaning
the pump has to be turned up high so causing these pressure differences
leading to cavitation.

The cure is to move the tank higher or convert to pressurised system.
Sometimes moving the pump to the flow side of the boiler fixes the problem
but this depends to a degree on the boiler design/size of waterways.
In days of yore, the pump was one the return side of the boiler which
promotes cavitation but boilers had bigger waterways then and pipework was
bigger.

It's been one thing after another with this heating system. Among other things, I removed an air separator and amended pipework near the pump last year as it was very tight and I was concerned it was restricting flow, causing/contributing to kettling in the boiler. I'd like to fix this issue in one move if possible.

There's only a couple of inches of water in the header tank when cold (which itself it only about four feet above the hot water tank). There's not much space to raise the tank in the attic, would raising the it a foot or so make much difference? Or should I just go for it an convert to a sealed system (I am nervous about it exposing weak joints in the pipework)? Could converting to a sealed system introduce other issues?

Thanks

"Tom Pickles" wrote in message
...
On Wednesday, November 26, 2014 8:19:50 AM UTC, harry wrote:
"Tom Pickles" wrote in message
...
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I
open the valve full, the noise goes, but turns up later at another rad.
They
generally only make a noise when the TRV's are closing as the room is
warm,
and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I
turn
the pump speed down, the noise abates somewhat, but the boiler starts
kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what
do
I need to do to get rid of it?

Thanks!

Reading your post again, cavitation seems quite likley.
The phenomenum occurrs when water pressure/head is too low.
You have an open vented sytem and it's worse upstair wher epressure is
lowest.

So the problem may be due to low head, your loft tank is not high enough
above the highest radiators or your pipework is on the small side meaning
the pump has to be turned up high so causing these pressure differences
leading to cavitation.

The cure is to move the tank higher or convert to pressurised system.
Sometimes moving the pump to the flow side of the boiler fixes the problem
but this depends to a degree on the boiler design/size of waterways.
In days of yore, the pump was one the return side of the boiler which
promotes cavitation but boilers had bigger waterways then and pipework was
bigger.

It's been one thing after another with this heating system. Among other
things, I removed an air separator and amended pipework near the pump last
year as it was very tight and I was concerned it was restricting flow,
causing/contributing to kettling in the boiler. I'd like to fix this issue
in one move if possible.

There's only a couple of inches of water in the header tank when cold (which
itself it only about four feet above the hot water tank). There's not much
space to raise the tank in the attic, would raising the it a foot or so make
much difference? Or should I just go for it an convert to a sealed system (I
am nervous about it exposing weak joints in the pipework)? Could converting
to a sealed system introduce other issues?

Thanks

Kettling is a form of cavitation but caused by localised hot water
temperatures made worse by pumping pressure reductions
Steam bubbles form and collapse which is what you hear.
A couple more things to check to reduce restrictions. Isolating valves on
the pump fully open ditto on boiler if fitted.
You might try rebalancing the system starting with all lockshield valves
fully open and closing them the minimum amount. You might be able to
rebalance the system and reduce the pump speed so curing the problem.
Zone valves/other motorised valves may not be fully opening. You are trying
to eliminate all negative pressures in the system by eliminating
restrictions.

Probably though the root of the matter lies in the boiler, it may be a
replacement for one with much bigger waterways.


Re how much to raise the tank? Anything would help but a small amount may
not be a total cure.
A foot "head" of water=0.43psi
Probably your best bet is to convert to sealed system and you can up the
pressure 'til the problems go away.

Pity really, it's added expense and something else to go wrong.
You can get a kit that includes the pressure relief/safety valve, tun dish
and the expansion vessel.
You'll have to site it where you can you can arrange a drain for the SV
outlet.

On Wednesday, November 26, 2014 9:34:16 AM UTC, harry wrote:
"Tom Pickles" wrote in message
...
On Wednesday, November 26, 2014 8:19:50 AM UTC, harry wrote:
"Tom Pickles" wrote in message
...
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I
open the valve full, the noise goes, but turns up later at another rad.
They
generally only make a noise when the TRV's are closing as the room is
warm,
and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I
turn
the pump speed down, the noise abates somewhat, but the boiler starts
kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what
do
I need to do to get rid of it?

Thanks!

Reading your post again, cavitation seems quite likley.
The phenomenum occurrs when water pressure/head is too low.
You have an open vented sytem and it's worse upstair wher epressure is
lowest.

So the problem may be due to low head, your loft tank is not high enough
above the highest radiators or your pipework is on the small side meaning
the pump has to be turned up high so causing these pressure differences
leading to cavitation.

The cure is to move the tank higher or convert to pressurised system.
Sometimes moving the pump to the flow side of the boiler fixes the problem
but this depends to a degree on the boiler design/size of waterways.
In days of yore, the pump was one the return side of the boiler which
promotes cavitation but boilers had bigger waterways then and pipework was
bigger.

It's been one thing after another with this heating system. Among other
things, I removed an air separator and amended pipework near the pump last
year as it was very tight and I was concerned it was restricting flow,
causing/contributing to kettling in the boiler. I'd like to fix this issue
in one move if possible.

There's only a couple of inches of water in the header tank when cold (which
itself it only about four feet above the hot water tank). There's not much
space to raise the tank in the attic, would raising the it a foot or so make
much difference? Or should I just go for it an convert to a sealed system (I
am nervous about it exposing weak joints in the pipework)? Could converting
to a sealed system introduce other issues?

Thanks

Kettling is a form of cavitation but caused by localised hot water
temperatures made worse by pumping pressure reductions
Steam bubbles form and collapse which is what you hear.
A couple more things to check to reduce restrictions. Isolating valves on
the pump fully open ditto on boiler if fitted.
You might try rebalancing the system starting with all lockshield valves
fully open and closing them the minimum amount. You might be able to
rebalance the system and reduce the pump speed so curing the problem.
Zone valves/other motorised valves may not be fully opening. You are trying
to eliminate all negative pressures in the system by eliminating
restrictions.

Probably though the root of the matter lies in the boiler, it may be a
replacement for one with much bigger waterways.


Re how much to raise the tank? Anything would help but a small amount may
not be a total cure.
A foot "head" of water=0.43psi
Probably your best bet is to convert to sealed system and you can up the
pressure 'til the problems go away.

Pity really, it's added expense and something else to go wrong.
You can get a kit that includes the pressure relief/safety valve, tun dish
and the expansion vessel.
You'll have to site it where you can you can arrange a drain for the SV
outlet.

I think I may well look more into converting to a sealed system. My understanding is that by converting, I am removing the ability for the heating system to create negative pressure, therefore remove the chance of cavitation, increasing flow and eliminating rad valve noise? Is this correct?

Thanks.

Tom Pickles wrote in
:

On Wednesday, November 26, 2014 9:34:16 AM UTC, harry wrote:
"Tom Pickles" wrote in message
...
On Wednesday, November 26, 2014 8:19:50 AM UTC, harry wrote:
"Tom Pickles" wrote in message
...
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of
it. I
f I
open the valve full, the noise goes, but turns up later at another
rad.

They
generally only make a noise when the TRV's are closing as the room
is

warm,
and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF.
If I

turn
the pump speed down, the noise abates somewhat, but the boiler
starts kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is
air, wh
at
do
I need to do to get rid of it?

Thanks!

Reading your post again, cavitation seems quite likley.
The phenomenum occurrs when water pressure/head is too low.
You have an open vented sytem and it's worse upstair wher epressure
is lowest.

So the problem may be due to low head, your loft tank is not high
enoug
h
above the highest radiators or your pipework is on the small side
meani
ng
the pump has to be turned up high so causing these pressure
differences leading to cavitation.

The cure is to move the tank higher or convert to pressurised
system. Sometimes moving the pump to the flow side of the boiler
fixes the prob
lem
but this depends to a degree on the boiler design/size of
waterways. In days of yore, the pump was one the return side of the
boiler which promotes cavitation but boilers had bigger waterways
then and pipework
was
bigger.

It's been one thing after another with this heating system. Among
other

things, I removed an air separator and amended pipework near the pump
las
t
year as it was very tight and I was concerned it was restricting
flow, causing/contributing to kettling in the boiler. I'd like to fix
this issu
e
in one move if possible.

There's only a couple of inches of water in the header tank when cold
(wh
ich
itself it only about four feet above the hot water tank). There's not
muc
h
space to raise the tank in the attic, would raising the it a foot or
so m
ake
much difference? Or should I just go for it an convert to a sealed
system
(I
am nervous about it exposing weak joints in the pipework)? Could
converti
ng
to a sealed system introduce other issues?

Thanks

Kettling is a form of cavitation but caused by localised hot water
temperatures made worse by pumping pressure reductions
Steam bubbles form and collapse which is what you hear.
A couple more things to check to reduce restrictions. Isolating
valves on



The "cavitation" expalnation fits with the situation I had. The noise
was from a turned down lockshield (on the fastest radiator). Since
having a sealed system it has not been an issue.

"Tom Pickles" wrote in message
...
On Wednesday, November 26, 2014 9:34:16 AM UTC, harry wrote:
"Tom Pickles" wrote in message
...
On Wednesday, November 26, 2014 8:19:50 AM UTC, harry wrote:
"Tom Pickles" wrote in message
...
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If
I
open the valve full, the noise goes, but turns up later at another rad.
They
generally only make a noise when the TRV's are closing as the room is
warm,
and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I
turn
the pump speed down, the noise abates somewhat, but the boiler starts
kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air,
what
do
I need to do to get rid of it?

Thanks!

Reading your post again, cavitation seems quite likley.
The phenomenum occurrs when water pressure/head is too low.
You have an open vented sytem and it's worse upstair wher epressure is
lowest.

So the problem may be due to low head, your loft tank is not high enough
above the highest radiators or your pipework is on the small side
meaning
the pump has to be turned up high so causing these pressure differences
leading to cavitation.

The cure is to move the tank higher or convert to pressurised system.
Sometimes moving the pump to the flow side of the boiler fixes the
problem
but this depends to a degree on the boiler design/size of waterways.
In days of yore, the pump was one the return side of the boiler which
promotes cavitation but boilers had bigger waterways then and pipework
was
bigger.

It's been one thing after another with this heating system. Among other
things, I removed an air separator and amended pipework near the pump last
year as it was very tight and I was concerned it was restricting flow,
causing/contributing to kettling in the boiler. I'd like to fix this issue
in one move if possible.

There's only a couple of inches of water in the header tank when cold
(which
itself it only about four feet above the hot water tank). There's not much
space to raise the tank in the attic, would raising the it a foot or so
make
much difference? Or should I just go for it an convert to a sealed system
(I
am nervous about it exposing weak joints in the pipework)? Could
converting
to a sealed system introduce other issues?

Thanks

Kettling is a form of cavitation but caused by localised hot water
temperatures made worse by pumping pressure reductions
Steam bubbles form and collapse which is what you hear.
A couple more things to check to reduce restrictions. Isolating valves on
the pump fully open ditto on boiler if fitted.
You might try rebalancing the system starting with all lockshield valves
fully open and closing them the minimum amount. You might be able to
rebalance the system and reduce the pump speed so curing the problem.
Zone valves/other motorised valves may not be fully opening. You are
trying
to eliminate all negative pressures in the system by eliminating
restrictions.

Probably though the root of the matter lies in the boiler, it may be a
replacement for one with much bigger waterways.


Re how much to raise the tank? Anything would help but a small amount may
not be a total cure.
A foot "head" of water=0.43psi
Probably your best bet is to convert to sealed system and you can up the
pressure 'til the problems go away.

Pity really, it's added expense and something else to go wrong.
You can get a kit that includes the pressure relief/safety valve, tun dish
and the expansion vessel.
You'll have to site it where you can you can arrange a drain for the SV
outlet.

I think I may well look more into converting to a sealed system. My
understanding is that by converting, I am removing the ability for the
heating system to create negative pressure, therefore remove the chance of
cavitation, increasing flow and eliminating rad valve noise? Is this
correct?

Thanks.

Exactly so.

On 26/11/2014 08:24, Tom Pickles wrote:
On Tuesday, November 25, 2014 10:45:03 PM UTC, John Rumm wrote:
On 25/11/2014 18:57, Tom Pickles wrote:
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)


Yup small bubbles through a nearly closed valve can make that sound.
Having said that, so could small particles of solid matter.

Has the system got enough inhibitor in it? (that will scavenge the
oxygen from the water, and slow the rate of corrosion which in turn
produces gas).

I did put plenty of Fernox inhibitor in when I last drained the system down and filled it.


A particulate filter may also be a good idea. Such as a fernox TF1 or
similar. These catch particulates and magnetic sludge.

I fitted a Spirotrap last year after I spent a weekend descaled the system using Fernox DS40 cleaner. I was having a lot of trouble with kettling in the boiler.

Sounds like you have the obvious bases covered then.

An auto vent valve somewhere in the system near its high point might
also be good.

Would an auto-venting rad bleed valve suffice, or should I fit something more like this?: http://www.screwfix.com/p/bottle-air-vent-15mm/34359

Sticking a vent on a vertical stub of pipe where the flow turns a corner
is usually good.




--
Cheers,

John.

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

"Tom Pickles" wrote in message
...
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I
open the valve full, the noise goes, but turns up later at another rad. They
generally only make a noise when the TRV's are closing as the room is warm,
and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I turn
the pump speed down, the noise abates somewhat, but the boiler starts
kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what do
I need to do to get rid of it?

Try turning the temp down on the boiler, it's boiling the water which can't
get around quick enough, you may have to open the TRV's to compensate for
the slightly lower temp.

On Tuesday, November 25, 2014 at 6:57:47 PM UTC, Tom Pickles wrote:
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I open the valve full, the noise goes, but turns up later at another rad. They generally only make a noise when the TRV's are closing as the room is warm, and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I turn the pump speed down, the noise abates somewhat, but the boiler starts kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what do I need to do to get rid of it?

I thought I'd post an update on this. After doing some research into converting my system into a sealed system after recommendations from replies in here (thanks all), it seemed like quite a lot of work with the prospect of creating leaks in the plumbing, and it wasn't giving me a sense of confidence. So I did some rooting about on the net and found these:

http://www.spirotech.co.uk/en/products/spirovent-rv2/

Managed to grab a brand new one off eBay for 80 quid delivered.

The ideal place to fit them according to the instructions is on the flow pipe, as near to the boiler as possible. So that's what I have done, and the results are exactly what I wanted. No more air in the system, no more noise, and hopefully a little increased efficiency.

Took me about an hour to fit including draining down and refilling. For the first few days you could hear it regularly venting large amounts of air. It has now calmed down and you can occasionally hear it let out a little air..

Hope this can help someone else in the future.

"Tom Pickles" wrote in message
...
On Tuesday, November 25, 2014 at 6:57:47 PM UTC, Tom Pickles wrote:
I've made a quick video with my phone of the issue:

http://youtu.be/NgEFMo-FfkM (20 secs)

The noise isn't that loud in the vid, but you can get the jist of it. If I
open the valve full, the noise goes, but turns up later at another rad.
They generally only make a noise when the TRV's are closing as the room is
warm, and it only affects upstairs rads.

I have an open vented system, running off a Glow-worm micron 50FF. If I
turn the pump speed down, the noise abates somewhat, but the boiler starts
kettling as the flow is too slow.

I'm guessing the problem is air, or my TRV's are crap. If it is air, what
do I need to do to get rid of it?

I thought I'd post an update on this. After doing some research into
converting my system into a sealed system after recommendations from replies
in here (thanks all), it seemed like quite a lot of work with the prospect
of creating leaks in the plumbing, and it wasn't giving me a sense of
confidence. So I did some rooting about on the net and found these:

http://www.spirotech.co.uk/en/products/spirovent-rv2/

Managed to grab a brand new one off eBay for 80 quid delivered.

The ideal place to fit them according to the instructions is on the flow
pipe, as near to the boiler as possible. So that's what I have done, and the
results are exactly what I wanted. No more air in the system, no more noise,
and hopefully a little increased efficiency.

Took me about an hour to fit including draining down and refilling. For the
first few days you could hear it regularly venting large amounts of air. It
has now calmed down and you can occasionally hear it let out a little air.

Hope this can help someone else in the future.


The problem you have is cavitation.
Steam bubbles forming and collapsing due to the reduced pressure in the
system caused by the pump.
The system is a bad design.
You might get round the problem by fitting a bypass valve which opens as
TRVs close.
http://www.screwfix.com/p/honeywell-...lve-22mm/34127