New Combi, dreadful noise from pipes!!

[Andy_Hat]

Hi everyone,
I am looking for some advice on my new boiler (just fitted 2 weeks ago) and the dreadful noises that I am now suffering with ,when i lived in a quiet house before......
I understand that my system is now pressurized so pipework is probably under more strain and the noise is likely pipes hitting joists.

The make of the boiler is Worcester Bosch (sorry not sure of model number) it is a combi boiler, wall mounted in my kitchen and was installed by Brit Gas.The boiler I had before was a Baxi back boiler and i didn't have problems with noise.

The problem that I have is at intermittent times of the day (often 6 in the morning and late at night) there is an almighty noise, not unlike someone starting to use a hammer drill ,it wakes me up (no doubt also wakes my neighbors) and lasts for several seconds.I am also getting a throbbing thudding noise when i put on the kitchen tap (Monobloc type) which is also intermittent but is by no means as much as a problem as the other noise (maybe they are part and parcel of the same problem?).

I have had B.Gas round who passed it over to Dyno-Rod who fitted new insides to toilet cistern which has actually made my problems worse (tap thudding noise came after this was done).

I have to fix this soon for I can't live with this noise ,it also appears to be coming from different parts of the house rather than in one specific area all the time.
My floors are laminated wood so i can't look at the pipe-work without destroying four floors (something i don't wish to do)
Can someone please advise what this problem might be caused by and how it can be cured.... if destroying the floors is my only option then so be it but at least i will know.
Maybe it's air,maybe it's a tap/toilet etc?
I am having another engineer round Saturday and would like to have some knowledge to hand rather than being fobbed off with something by them that might not be my only option or that is incorrect.

All ideas happily welcomed I have trawled the forums looking for answers to no avail!

Many thanks in advance
Andy

 

[gas_man_gaz]

if its happening wen ya using the taps it could be water hammer, on some installation they fit a mini exspansion vessel to the cold mains to absorb the shock so its not as noisy.. jus a thought

 

[Andy_Hat]

if its happening wen ya using the taps it could be water hammer, on some installation they fit a mini exspansion vessel to the cold mains to absorb the shock so its not as noisy.. jus a thought

Thanks for that
That is something to think about that might work,I wonder if the tap noise(if it is water hammer) is somehow interlinked with the dreadful row that happens for no apparent reason at anti-social times of the day or night?

I am really hoping that all problems might come from one simple source and the addition of something like a mini expansion vessel might cure all?

 

[fingertight]

hello people, just sumbled on this site, very impressed with the pool of knowledge I can dip my toes in here.

Sounds to me like the cold mains have been disturbed during installation process, (connecting cold pipe up to boiler) ive had it a few times, cold pipe hasnt been tampered with for years, as soon as its disturbed you get the "thudding noise", settles down after about a year (i know, you'll be evicted by then) It will be worse on early mornings as the mains pressure is generally higher at this time (less people using) and there are more "pressure spikes". I would check that the rising main is properly clipped and secure first, clip every 1/2mtr on horizontal, 1mtr on vertical. If it is, you could try a "shock arrester", as gas man mentioned, its around the size of an apple and absorbs any pressure surges, ive used em on 3 seperate occasions, havent let me down yet. you can get them from Plumb ctr. In the mean time, if its bad, try turnin your mains off at night, this will stop it. MAKE sure you turn it back on when you get up before drawing water off though.
[/i]

 

[Andy_Hat]

hello people, just sumbled on this site, very impressed with the pool of knowledge I can dip my toes in here.

Sounds to me like the cold mains have been disturbed during installation process, (connecting cold pipe up to boiler) ive had it a few times, cold pipe hasnt been tampered with for years, as soon as its disturbed you get the "thudding noise", settles down after about a year (i know, you'll be evicted by then) It will be worse on early mornings as the mains pressure is generally higher at this time (less people using) and there are more "pressure spikes". I would check that the rising main is properly clipped and secure first, clip every 1/2mtr on horizontal, 1mtr on vertical. If it is, you could try a "shock arrester", as gas man mentioned, its around the size of an apple and absorbs any pressure surges, ive used em on 3 seperate occasions, havent let me down yet. you can get them from Plumb ctr. In the mean time, if its bad, try turnin your mains off at night, this will stop it. MAKE sure you turn it back on when you get up before drawing water off though.
[/i]

And very impressed with your knowledge too fingertight...
I was rather worried by your reference to disturbing cold water pipes that had laid dormant many years ,giving me thoughts that somehow bad water spirits had been messed about with in my house and were now going to haunt me for the next year
I must say that the thought of turning my mains off every night for a year is not a pleasant one (but a good short term one) and that i was hoping for something a little more immediate ,does this arrestor offer any hope for me as an immediate solution? It's certainly starting to sound like it might be the answer I wonder if the nice man from B.gas will have one on him that he would like to fit for me at no extra charge?

I am also a tadge confused by the fact that now i have a "sealed" heating system how the peaks and troughs of neighbouring water users would make a difference to my water?
The noise is quite bad at all sorts of times and was being particularly "musical" earlier on at around 8pm tonight funnily enough it's quite hard to pin-point exactly where it comes from and I was rushing around the house trying to trace it when it started up (always just too late getting there of course)
I greatly appreciate your input all other ideas are welcomed but it's looking like the arrestor idea is perhaps the answer I am hoping....
Andy

 

[Gasguru]

You say it can start at random when you are not even operating any taps etc.

Have you got flush valves or flapper valves fitted to any WC's (as opposed to traditional syphons). Its posible these are leaking water into the pan so from time to time the float valves in the WC cistern open a little to fill. If pipework is poory clipped water hammer may ensue.

Another reason, do you share the mains connection with other flats/properties. Perhaps they have problems with hammer and its transmited through to your pipework. Before with the old setup its likely the mains only supplied the kitchen sink cold tap and the tanks in the roof, now of course all taps/float valves are off the mains (if it done properly).

 

[Andy_Hat]

You say it can start at random when you are not even operating any taps etc.

Have you got flush valves or flapper valves fitted to any WC's (as opposed to traditional syphons). Its posible these are leaking water into the pan so from time to time the float valves in the WC cistern open a little to fill. If pipework is poory clipped water hammer may ensue.

Another reason, do you share the mains connection with other flats/properties. Perhaps they have problems with hammer and its transmited through to your pipework. Before with the old setup its likely the mains only supplied the kitchen sink cold tap and the tanks in the roof, now of course all taps/float valves are off the mains (if it done properly).

Hi Gasguru,thanks for your input...
coincidentally the first engineer who came round made exactly the same diagnosis as yourself and (apologies for incorrect terminology) replaced the gubbins in the downstairs loo for it was one of those loos without an overflow pipe and was indeed overflowing very gradually into its basin .Unfortunately this didn't fix the problem and in fact was the beginning of the thudding sound problem on my kitchen tap after toilet innards were changed.
The plumbing in this house is quite "unique" (bodged to be precise) and even before the combi was fitted both toilets ran off mains as did all cold water taps in the house/garden.I don't think that properties water pipes are linked, though i do know that next door has the same mains supply connection from the road as I do.
There seems to be little pattern to the noise and it hasn't made one sound in the last three hours even after taps being used ,toliets flushed ,shower run etc It almost seems like it is a build up that happens gradually resulting in a crescendo of banging pipework that i am sure i will be hearing in a short while whilst trying to be asleep grrrrrrrr
cheers
Andy

 

[Gasguru]

If you have any isolating valves fitted try isolating taps/float valves etc to isolate and locate the problem. You could isolate all the hot pipework from the boiler by closing the cold inlet valve to the boiler.

Does the washing machine have a hot fill hose connected - if so you could isolate the hot valve (sometimes the WM solenoid valves can let by a little.) so see if any effect.

Does the boiler have a comfort mode (pre heat mode)? If so turn it off (eco on some models). Perhaps the pressure in your hot pipework increases considerably as the boiler plate exchanger is heated up to provide the quicker hot draw off. Check the mains stopcock is fully open to allow backflow of expanded water.

 

[Andy_Hat]

If you have any isolating valves fitted try isolating taps/float valves etc to isolate and locate the problem. You could isolate all the hot pipework from the boiler by closing the cold inlet valve to the boiler.

Does the washing machine have a hot fill hose connected - if so you could isolate the hot valve (sometimes the WM solenoid valves can let by a little.) so see if any effect.

Does the boiler have a comfort mode (pre heat mode)? If so turn it off (eco on some models). Perhaps the pressure in your hot pipework increases considerably as the boiler plate exchanger is heated up to provide the quicker hot draw off. Check the mains stopcock is fully open to allow backflow of expanded water.

Hi again Gasguru and thanks for your ideas....
The stop cockhas been on full and I have had the boiler on eco mode since installation.
Being a humble non plumber I am a bit unsure of what it is you think I should try with the washing machine it has two rubber tubes a red and a blue one coming into it (hot and cold) are you suggesting disconnecting the hot one ?(flipping the red switch)
I understand that isolating some of these things would be a good idea and I know i have an isolation vavlve on the upstairs toilet and can have a look for some more valves and turn them off for a while in turn to see if it works as a problem fix.
I will be having an engineer round from BG tomorrow and hope to be armed with possibilities supplied by you good people at least i may be able to isolate the problem for him if I try turning stuff off for a while
thanks again
Andy

 

[Andy_Hat]

Additional Info people.....
After looking at my boiler handbook the boiler model number appears to be Worcester Bosch Greenstar 25si/30si maybe this might help?

 

[fingertight]

Hi Andy, youve got alot to run with now with all the replys! from your notes the thudding occurs when your heating is off, if your taps and b.valves were fine the day before the installation and there was no noise. .then its not them

By saying that the cold main has been disturbed i mean pysically cut, pulled and pushed to link it up to the cold feed to the boiler, this, along with the main stop tap being closed & opened for the first time in ages can cause the thudding (its happened to me..funny enough, once, after fitting a 25si myself. . no. .i didnt fit yours!)its also happened fittin cisterns etc.. If i was you i would...
1. turn the boiler off for a night..if it stops then its your boiler. .BG to sort.
2. if it continues with boiler off then its cold main.(suppose you could still argue its thier fault)
from this point you can try..1/4 turning stop tap towards off over couple of nights, very un-likely to work as flow rate would be reduced but not standing pressure.
If the cold mains, in the area where BG cut into it is sufficently clipped, then a shock arrester would be a good option, or get in a witch doctor for those bad spirits.

 

[markplumb]

you've had a new boiler fitted so im guessing get your installer back to remove the dead legs(pipes no longer used) to where the old cylinder was.

 

[Andy_Hat]

Firstly i would just like to say a huge thank-you to all those who have given me their precious time and valuable experience in bothering to reply to my current situation.
I have the engineer coming from the hours of 8 and 13:00 tomorrow and watches are synchronised and my attack is planned!

My latest situation is the upstairs toilet is turned off at the special turny off screw on the pipe (you can tell I should have been a plumber I now know all the terminology ) and I am listening like a hawk for sounds of pipe trouble,drinking beer, fingers crossed (pathetic really)

The downstairs monobloc in the kitchen is still making the thuddy noise (only when the hot and cold are on together incidentally ) so not sure if I have done anything constructive apart from having to relieve myself of lager in the downstairs loo through the night.

Even if this gets fixed tomorrow..... I will be back to aid my fellow humans with the outcome
Once again thanks and i raise a glass to you all!

 

[gas4you]

Have you checked that the cold mains stop cock has been opened fully?

 

[Andy_Hat]

Have you checked that the cold mains stop cock has been opened fully?

Yes it is ,fully open, with a quarter turn back

Incidentally... apart from one loud bang earlier ,things seem quieter now that the upstairs loo's isolation valve is turned off,
but that just might be a coincidence?
Andy