Noise in central heating system back!

[Ted808]

Hi Guys,

I have a problem I need advice on please...
I've replaced an old Keston that had seen better days,
with a Worcester + unvented cylinder, the central heating had an added expansion vessel.
Biggish house 17 rads. Y plan layout. TRV's all rads apart from bathroom.

The problem they had before was that they had to continually top up the ch pressure, and noise, sounding through the house- I suspected the old boiler pump being knackered and sludge.

It all worked fine and, no noise ...... for a month! Now to my horror the noise is back.

I fitted an ABV and dropped the EV to that of the boiler.

What can I do now?
Have I set the ABV too high?
I wondered if the old TRV's aren't bi-directional?
Pipes under the floors not supported?
3 port valve squealing?
Some more cleaning, drain down and change TRV's???
:001_9898:

 

[AWheating]

First check the abv, check the prv has no been opening due to expansion to small/ they have topped up pressure? What trv's are fitted?

if the noise is when the hot water is used service and check combi valve.

 

[Ted808]

First check the abv, check the prv has no been opening due to expansion to small/ they have topped up pressure? What trv's are fitted?

if the noise is when the hot water is used service and check combi valve.

Cheers AW... but abv is new and I've found out noise is old, before old boiler got moved, and before new boiler- it stopped for only a few days after install. Mostly honeywell trv's tho there's one or two no name ones.
Noise only with CH... scratch scratch!

 

[hammers4spanner]

Try shutting off certain rads see if noise continues

 

[Ted808]

Updating some old threads- the answer to noise was eventually found to be a connection between the flow and return- a feature that was left from the old system, which was gravity fed!
I never saw it, they had the plumbers who did the bathroom take a look. Apparently, this is what I said anyway, that it was under the tiled bathroom floor, but, they had to take down some plasterboard to actually get to it. live and learn or not!?