Unexplained noise in pipework Help and information on all topics relating to your central heating, air conditioning and ventilation issues.

[DAVEYD]

There has been noise in the pipework between pump and boiler when water starts to heat for sometime and on return from a week break with CH off found boiler not working and clicking sound from diverter valve above pump adjacent to cylinder. Reset boiler which fired but did not heat water. Set timer to off and ticking persisted overnight. BGAS engineer called and changed pump but could not identify noise in pipework. He thought it might be debris moving in system and left quotation for Magnaclean. There are not other apparent faults in system.
I would be grateful if anyone can confirm his diagnosis or suggest other explanation for noise in pipes and whether Magnaclean would offer a solution. I quite like the idea of Magnaclean and have read good reports of it.
DIY explanation may not help as I am very inept at plumbing/electrics
With thanks in advance for responses

[htg engineer]

I think he's changed the pump for no reason, if the timer was set to off the pump should not be running so how would debri's be moving around the system ?

The ticking noise sounds like the actuator, often happens - replace the actuator as it is on it's way out.


htg

[DAVEYD]

Thanks for response htg eng. I think I may have not expressed myself properly.
The noise in the pipework happens only when the system is on and usually eases off after a while but returns when hot water is run.
The ticking noise was when the system was off and again after I had reset the boiler. Prior to the engineer visit I had turned on the electric immersion and the ticking had stopped and did not return when electric immersion turned off. I did not retry CH before engineer visit and all seemed OK except for noisy pipes when he visited. Could debris which had somehow blocked the diverter whilst we were away as I understand the pump runs for a few minutes everyday even when timer is off