Combi noise

Blackett · 21 May 2006

I am just having a Worchester 40E combi installed.
At the moment I have two questions before the work is complete and I pay the installers.

1) The pump is still circulating the central heating water when the 'flame is off' and the system has reached it's required temperature - this normal? (setting is on comfort)
2) Very often some radiators make a whoosing / flowing noise which is similar to a toilet filling noise but lot quieter. This normal ? (stops when I alter the thermostat on the radiator).

This is the first time I have had a combi and used to a stored water type system.
I have very limited knowledge as you may have guessed. Any advice would be gratefully received.

Gary59 · 21 May 2006

Apologies, but you say you are having a combi installed, then you go on to explain the problems so far as you see them. Have the installers finished.......? If not why not wait until they are, before worrying that the new combi is faulty is some way....?

Just a suggestion...!

Paul Barker · 21 May 2006

Pump stays on a short while to dissipate the heat, and boiler fires occasionally to ensure you have instant hot water.

TRV's make hissing sound when they are restricting the flow, but not fully shut. Make juddery banging sound when orientated the wrong way, but I don't think there are any left which are not bi directional.

Good boiler, shower should hose you out of the bathroom.

Blackett · 21 May 2006

They are just about to finish and was not 100% happy with their explanation of things. They seemed to be 'finding their way through installation' which did not bode me with confidence.

Thanks for the responses, it seems that combi boliers are just a little more noiser in their operation that what I am used to.

Cheers

Agile · 21 May 2006

Regarding the noise as the TRVs are closing!

There should be an automatic bypass fitted to the system. Under the Energy Efficiency regulations this is now required in most cases.

Either they have not bothered or more likely did not know it was required or if its fitted it needs adjusting.

Why are some installers of such low calibre? I went to a new boiler which had been fitted in only 6 hours. The fitter had noticed the gas supply was only 17 mB and had not bothered with the Benchmark.

A quality installer will explain the system components and list them on the quotation and show you how to use the controls before he completes the Benchmark Certificate (???)

Tony

Blackett · 21 May 2006

How do I know if 'an automatic bypass' has been fitted to reduce the valve closure noise?

Paul Barker · 21 May 2006

Ask the fitters if there is an auto bipass.

I can respect them finding their way through the installation, I fitted just one of those boilers about 18 months ago and am going to fit my second in June. All the time between then and now I have been fitting 28kw and 30kw combis even the odd 24, and 19 kw regular boilers all of varied manufacture Buderus, Potterton, Vokera and the occasional customers own Biasi, Ravenheat, bought off a shelf at a shed.

Give me a boiler of my choice and I won't need to open the instructions, but when I do that 40kw W in June I'll be going through the pages with a fine tooth comb. Actually if I remember right it's an easy manual to follow compared to the Buderus, which is best ignored, great boiler, sensibility lost in translation from Dutch.

ChrisR · 21 May 2006

There should be an automatic bypass fitted to the system.

Oh no there should not!
These boilers have an automatically variable pump.

One radiator (the one which would most affect the thermostat) should not have a trv and must be left open.

doitall · 21 May 2006

A by-pass circuit must be installed if the manufacturer requires one or specifies that a minimum flow rate has to be maintained while the boiler is firing. The system by-pass circuit must then include an automatic by-pass valve, (not a fixed-possition valve)

ChrisR · 21 May 2006

Adopting Rimmer/ Ken Livingstone sort of whine.....
What is it?
Was there something a teeny bit ambiguous about what I wrote?
Now I really don't think there was.

Way to go, PAUL!

You can probably quieten the valves by reducing the flow of water going through them ( usually done at the lockshield (ie other) end) . Some installers leave then wide open with no attempt at balancing or making sure the rec flow isn't exceeded.

Blackett · 21 May 2006

So basically you can reduce the flow to the radiators at the combi?
which wont effect flow rate to the taps I presume, as different? - cos I need the 16L min due to big house etc.

doitall · 21 May 2006

Just make sure he fills all the paperwork out including the Logbook with all the tests before you pay him.

Blackett · 21 May 2006

This a log book which comes with the Boiler for warranty or his own that comes with the CORGI cert?

As a person who has never been through this before - I dont even know what paper work I should be getting at the end !

Help.....

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Combi noise

Similar threads