One of my radiators (bathroom - Twinfast valve - Worcester Highflow
Heatslave Boiler- 22 years old) makes a noise as though loads of air is
getting into it - especially after the boiler diverts back to C/H after a
bath / shower.

However, when I check the bleed valve there is never any air.

What is going on? It sounds like loads of air is entering at times.

"John" wrote in message
...
One of my radiators (bathroom - Twinfast valve - Worcester Highflow
Heatslave Boiler- 22 years old) makes a noise as though loads of air is
getting into it - especially after the boiler diverts back to C/H after a
bath / shower.

However, when I check the bleed valve there is never any air.

What is going on? It sounds like loads of air is entering at times.



How much water are you taking out the bleeder when you check it? You will
also have to keep topping up the boiler pressure after you have bled the
system, how is this done, and to what setting on the gauge are you choosing?
What diameter of pipework is feeding this radiator and does it have any
tight bends near to the radiator?

Sometimes a radiator can just do this type thing and there are many causes
why it does. A simple piece of plumbers thread tape had us going crazy when
our system was first installed. A little bit of the tape had slipped over
the edge of one fitting and was acting like the reed on a clarinet when the
water moved through the pipework. Took us two weeks to find out where it
was, because the sound also travelled along the pipes.

If there is a little imperfection in the construction of a valve, or on the
radiator itself, it can cause the water to swirl around inside. This can
sound like air is being forced through the system. With the boiler Stat'
turned off, try running the system and put your ear on the area you think is
causing the problem. I ask you to turn the heat off to do this, because I
don't want you in casualty with third degree burns to your face.

Listen to the water flow around the system and, if you are listening
carefully enough, you might actually be able to hear exactly where the sound
is coming from. It may actually be at a bend under the floor Etc. Or in a
fitting further down the line from the radiator the noise is most noticeable
at.

Your system seems to working OK otherwise, or you'd have mentioned other
faults with it. So it seems like it is not causing any major problem and is
just a nuisance noise. Unless it gets worse or other symptoms appear, I'd
advise you to forget all about it.

Hope this helps a little.

"BigWallop" wrote in message
om...

"John" wrote in message
...
One of my radiators (bathroom - Twinfast valve - Worcester Highflow
Heatslave Boiler- 22 years old) makes a noise as though loads of air is
getting into it - especially after the boiler diverts back to C/H after a
bath / shower.

However, when I check the bleed valve there is never any air.

What is going on? It sounds like loads of air is entering at times.



How much water are you taking out the bleeder when you check it? You will
also have to keep topping up the boiler pressure after you have bled the
system, how is this done, and to what setting on the gauge are you
choosing?
What diameter of pipework is feeding this radiator and does it have any
tight bends near to the radiator?

Sometimes a radiator can just do this type thing and there are many causes
why it does. A simple piece of plumbers thread tape had us going crazy
when
our system was first installed. A little bit of the tape had slipped over
the edge of one fitting and was acting like the reed on a clarinet when
the
water moved through the pipework. Took us two weeks to find out where it
was, because the sound also travelled along the pipes.

If there is a little imperfection in the construction of a valve, or on
the
radiator itself, it can cause the water to swirl around inside. This can
sound like air is being forced through the system. With the boiler Stat'
turned off, try running the system and put your ear on the area you think
is
causing the problem. I ask you to turn the heat off to do this, because I
don't want you in casualty with third degree burns to your face.

Listen to the water flow around the system and, if you are listening
carefully enough, you might actually be able to hear exactly where the
sound
is coming from. It may actually be at a bend under the floor Etc. Or in
a
fitting further down the line from the radiator the noise is most
noticeable
at.

Your system seems to working OK otherwise, or you'd have mentioned other
faults with it. So it seems like it is not causing any major problem and
is
just a nuisance noise. Unless it gets worse or other symptoms appear, I'd
advise you to forget all about it.

Hope this helps a little.


My system is gravity fed.

I will try running it cold - but I suspect it may be related to the temp of
the boiler. As I say - there is never any air. It sounds a bit like air
being forced through a tight space. Will try opening lockshield full to see
what happens as well.