We' ve recently replaced an aging Gloworm cast-iron boiler with an Ideal
Response 120 combi. It works fine, apart from some noises.

Most of the radiators are fitted with thermostatic valves (only one radiator
is not). When a valve upstairs is on the point of closing, it seems to set
up a horrendous vibrating noise, that can be felt and heard through the
whole house, but loudest at the value. If I switch the value up or down a
little, so it is fully on or off, the vibrating stops.

The vibration seems to resonate around 20 to 30Hz - but that's just an
estimate - it is very loud though. It happens on several of the valves, but
not all.

We don't have any cold spots or radiators that don't heat up. We also never
had this problem on the old boiler (though it did sound like a giant kettle
boiling and thumping around). Switching on a hot tap stops the vibration,
for as long as it is on. I have no idea why that should be, as the taps and
radiators should be independant.

I was just wondering what the problem could be, and how I could go about
confirming and/or fixing it.

Thanks,

-- Jason
(newbie here)

On Tue, 03 May 2005 19:54:54 GMT, "Jason Judge"
wrote:

We' ve recently replaced an aging Gloworm cast-iron boiler with an Ideal
Response 120 combi. It works fine, apart from some noises.

Most of the radiators are fitted with thermostatic valves (only one radiator
is not). When a valve upstairs is on the point of closing, it seems to set
up a horrendous vibrating noise, that can be felt and heard through the
whole house, but loudest at the value. If I switch the value up or down a
little, so it is fully on or off, the vibrating stops.

The vibration seems to resonate around 20 to 30Hz - but that's just an
estimate - it is very loud though. It happens on several of the valves, but
not all.

We don't have any cold spots or radiators that don't heat up. We also never
had this problem on the old boiler (though it did sound like a giant kettle
boiling and thumping around). Switching on a hot tap stops the vibration,
for as long as it is on. I have no idea why that should be, as the taps and
radiators should be independant.

I was just wondering what the problem could be, and how I could go about
confirming and/or fixing it.

Thanks,

What have setting do you have on the non-thermostatic radiator, this
sounds to me as if the system is overheating. Some Combi's have a pump
over-run which allows any excess heat to be removed from the boiler
and into the system, you old cast iron boiler wouldn't have needed
such a thing, the designers allowed for the excess heat.

J

In article ,
"Jason Judge" writes:
We' ve recently replaced an aging Gloworm cast-iron boiler with an Ideal
Response 120 combi. It works fine, apart from some noises.

Most of the radiators are fitted with thermostatic valves (only one radiator
is not). When a valve upstairs is on the point of closing, it seems to set
up a horrendous vibrating noise, that can be felt and heard through the
whole house, but loudest at the value. If I switch the value up or down a
little, so it is fully on or off, the vibrating stops.

This happens when valves are installed with the water passing
through in the wrong direction. Many valves are bi-directional
nowadays, but if yours isn't (should be an arrow on the valve
body), then it wants moving to the other end of the radiator
or turning round the other way (so the body is horizontal if
it's currently vertical), if the valve connections are
reversible for such mounting.

Another thought -- maybe the pump's dynamic pressure is rather
high. You haven't shut off the radiator with no TRV have you?
It might also be that the pump could be turned down a notch,
but that should really only be done if you can check the flow
through the boiler is still adequate.

--
Andrew Gabriel

"John_ZIZinvalid" wrote in message
...
...
I was just wondering what the problem could be, and how I could go about
confirming and/or fixing it.

Thanks,

What have setting do you have on the non-thermostatic radiator, this
sounds to me as if the system is overheating. Some Combi's have a pump
over-run which allows any excess heat to be removed from the boiler
and into the system, you old cast iron boiler wouldn't have needed
such a thing, the designers allowed for the excess heat.

I set the heating temperature (on the boiler) down to its minimum, but the
radiators still get fairly hot - perhaps the thermostat in the boiler is not
working?

The non-thermostat radiator was down fairly low. I've turned that up now, to
see if it makes a difference. That radiator also happens to be very close to
the boiler (which is why I think it was low). I'm not sure if that makes any
difference - I guess it can still lose roughly the same amount of heat,
regardless of whether it is next to the boiler or at the other end of the
house, assuming the pipes are well lagged. But I can change that if you
think it would help.

The cooling offered by switching on a hot tap makes sense now. Thanks.

-- JJ

Most of the radiators are fitted with thermostatic valves (only one
radiator
is not). When a valve upstairs is on the point of closing, it seems to set
up a horrendous vibrating noise, that can be felt and heard through the
whole house, but loudest at the value. If I switch the value up or down a
little, so it is fully on or off, the vibrating stops.

The vibration seems to resonate around 20 to 30Hz - but that's just an
estimate - it is very loud though. It happens on several of the valves,
but
not all.

Had this problem with a builder (but a grotty plumber) who put the
thermostatic valves on at random and some have the water flow the wrong way.
Previous posts here indicate that some valves work both ways round, some
don't and vibrate causing the pipes to transmit the sound round the house.

rusty.

"Andrew Gabriel" wrote in message
.. .
In article ,
"Jason Judge" writes:
We' ve recently replaced an aging Gloworm cast-iron boiler with an Ideal
Response 120 combi. It works fine, apart from some noises.

Most of the radiators are fitted with thermostatic valves (only one
radiator
is not). When a valve upstairs is on the point of closing, it seems to
set
up a horrendous vibrating noise, that can be felt and heard through the
whole house, but loudest at the value. If I switch the value up or down
a
little, so it is fully on or off, the vibrating stops.

This happens when valves are installed with the water passing
through in the wrong direction. Many valves are bi-directional
nowadays, but if yours isn't (should be an arrow on the valve
body), then it wants moving to the other end of the radiator
or turning round the other way (so the body is horizontal if
it's currently vertical), if the valve connections are
reversible for such mounting.

Another thought -- maybe the pump's dynamic pressure is rather
high. You haven't shut off the radiator with no TRV have you?
It might also be that the pump could be turned down a notch,
but that should really only be done if you can check the flow
through the boiler is still adequate.

Possibly it is a combination of the two: some valves have been fitted
backwards, and the new pump is more powerful, triggering a vibration that
was not a problem before. I thought that perhaps the new boiler had been
fitted the wrong way around, but it does flow the same way as the old pump.
It's all a bit of a mystery how so many of the TRVs are fitted backwards - I
think a weekend job draining and refitting is in order ;-)

Thanks for the tips.

-- JJ

"Rusty" wrote in message
...



Most of the radiators are fitted with thermostatic valves (only one
radiator
is not). When a valve upstairs is on the point of closing, it seems to
set
up a horrendous vibrating noise, that can be felt and heard through the
whole house, but loudest at the value. If I switch the value up or down
a
little, so it is fully on or off, the vibrating stops.

The vibration seems to resonate around 20 to 30Hz - but that's just an
estimate - it is very loud though. It happens on several of the valves,
but
not all.

Had this problem with a builder (but a grotty plumber) who put the
thermostatic valves on at random and some have the water flow the wrong
way.
Previous posts here indicate that some valves work both ways round, some
don't and vibrate causing the pipes to transmit the sound round the house.

Yes - I have identified three of the valves fitted the wrong way around -
and all vibrate now when on the point of turning on or off. They sound like
four hefty builders hitting a radiator with a pick-axe handle each. I'll
leave these off until I get a chance to reverse them.

Thanks for the info. This has given me a good excuse to read the service
manual for the boiler, at least. Lots of interesting tips on balancing and
the reasons for at least one radiator without TRVs (and tells me that the
one radiator without one, is probably *too* close to the boiler).

-- JJ