Help with noisy hot water heating loop

[marc1977]

Whats weird is that:

a) the noise from pipes is only present when the hot water is on alone. As soon as i switch the central heating on it disappears?!

b) Its a pressured system with no visible leaks so how come i have to bleed one of the rads for 2-3 seconds every week?! I've also checked the expansion tank overflow and there is no water discharge from there.

 

[kris]

Is the noise only heard near the tank ?

 

[marc1977]

Kris,

No, the ting ting noise is coming from the 22mm pipes near the boiler. Sounds like air in them to me but this doesn't really make sense (see above)

 

[lame plumber]

turn the circ pump down a notch and try adjusting the bypass as well if it only happens on hw it is probably down to too high circ rate on smaller circuit and just needs adjusting.

 

[townfanjon]

Excellent, you both sound like you know what you're talking about!



Marc

Forgive me Marc , I aint taking the pi** , Its the funniest thing I have heard today , YES they certainly do lol

 

[Last Plumber]

I agree with Lame.
You could try adjusting the Balancing valve a bit too on the cylinder coil.
Try half way open if it's 22mm

 

[marc1977]

Right, I have Rubbish the gate valve off slightly and it seems to have stopped the noise! Thank you all.

Anyone any idea on how i can be getting air into a sealed system but dont have a leak? only a small amount but its there...

 

[Last Plumber]

Right, I have **** the gate valve off slightly and it seems to have stopped the noise! Thank you all.

Anyone any idea on how i can be getting air into a sealed system but dont have a leak? only a small amount but its there...

It may not be air, it could be hydrogen !
By product of corrosion ?
Did you have rads changed when pipe work was changed to two pipe?

 

[marc1977]

Yeah all rads except 1 were changed. Ive tried setting the air on fire but didnt ignite!