Hi there, any one out there know how to cure my central heating noise? Turn it on in the morning and for the first ten minutes it's fine. Then it starts to make the expansion pipe vibrate causing it to knock. As the heating warms up the noise reduces quite a lot, but doesn't completly disappear.
I thought it could be kettling, but as the noise reduces and doesn't get worse, then I think not. Also I've put some additive in the system to cure the kettling effect, but to no avail.:confused:
Any suggestions?

Thanks

Spinner

what model is the boiler.?

i had one last week that did this it ended up being a few things ..
pump full of crud..(new pump)
and heat exchange needed power flushing .

sounds as good as new now. :)

Thanks for the reply so quickly.

The model of the boiler is a " Potterton Housewarmer 45 or 55 "

If the pump is full of muck, then the water in the system, I would of thought would be dirty. When I bleed the system and when I drained out some water to put the additive in, the water was as clear as tap water.
If the heat exchanger requires a power flush, does this require dismantling the boiler?Also wouldn't the noise get worse as the system gets hotter, rather than the noise reducing?

Thanks

spinner

You could always try a quick scout through this site - they have solved many diy/house problems for me.

http://www.diynot.com/

You could always try a quick scout through this site - they have solved many diy/house problems for me.

http://www.diynot.com/

yes a cracking forum.. drop a post on there ... they are like boiler gods . :)

Hi,

I have exactly the same problem as you. Did you manage to sort it, if so what did you do?

Regards,

Bigsul.

you can flush the boiler, drain the system down and cut in the power flush to the boiler and flush with the correct flushing agent, i use kamco fx2 on most.

even if the water is clear it may still be a siezed pup.

My problem started only after I cleaned the system out, flushed it 4 times then filled up with inhibitor, leak sealer and noise silencer.
It was fine before that, just some boiler roaring. Now it chuffs like a train and the pipes bang like a good un.

Bigsul.

gulp ! i would chuff and bang to if you filled me with all that rubbish lol..

noise reducer and sealer are a total waste of money, a clean sysem would only ever need inhibitor and the correct amount.

Do you think I should drain and flush the system again, clean out with DS-40?

Regards,

Bigsul.

i would look at 2 things . either blocked heat exchange or needs a pump.(not sure about the pump but it wont hurt to swop it if old 30 pound from screwfix)

sounds like kettling were it is usually narrowing of the water ways in exchange, i have had lots of success with power flushing to cure this,

a chemical flush wont do anything to fix the problem here, (were u empty a bottle of restore in a rad then drain out 2 days later)

here (http://www.kamco.co.uk/GuidanceNotes/PDF/CF90instructions.pdf) is how to use 1.

most hire companies rent them out if you want to fix this your self.

other info is here (http://www.kamco.co.uk/index2.htm)

I agree about the heat exchanger, and my pump is brand new. I changed it a few weeks ago.
If I get a powerflush I'll probably hire one, might try a chem flush first as its only since I put the additives in that the banging has started. Its only 15 or so quid wasted if it doesn't work.
I am leaning toward a powerflush though, at least you know its really clean if you do one.
I'll keep you posted on here.

I may be missing the point here but I think its airlocked somewhere. turn all rads on and off one by one see if that cures it.

I may be missing the point here but I think its airlocked somewhere. turn all rads on and off one by one see if that cures it.

If it was airlocked, wouldn't one of the rads be cold?

I have turned all the rads off before, tried allsorts.


I'm still wondering what to do. The worst of the noise has stopped, but I know its still not right.
It does seem to be low flow through the HE, that would fit perfectly. It could be anything though I guess?

Bigsul.

Please explain what you mean by HE ?
For an airlock a rad does not, not have to work.
There are other ways to get them out but you have to be gas registered because you have to go inside the boiler.

Please explain what you mean by HE ?
For an airlock a rad does not, not have to work.
There are other ways to get them out but you have to be gas registered because you have to go inside the boiler.

Hi,

Sorry for the delay.

HE is Heat Exchanger (in the boiler).
Could there be an airlock in the boiler?

Bigsul.

IT could be air their but I doubt it. If your still unsure best to get a heating engineer to look at it ? post your area to get best local engineer.

Hi,

Sorry for the delay.

HE is Heat Exchanger (in the boiler).
Could there be an airlock in the boiler?

Bigsul.

i dought it but as ever anything can happen :)