Banging Boiler Noise.

[nmfeb70]

Hi, I have a Worcester 28i Junior combi which is serviced regular. When I switch it on and then flush the toilet or run a cold tap it gives off banging and clunking noises. I must point out that this only happens within ten minutes of starting the boiler up, after that the noises disappear.
Any suggestions before I splash out on inhibitor? Thanks.

 

[Steelmasons]

Check/replace sump pump.

 

[45yearsagasman]

Any suggestions before I splash out on inhibitor?

Inhibitor wont fix your problem.

 

[gas112]

tenner for inhibitor now that really splashing out