noisy pipes

[jayjay]

Hi new to forum, hope you can help. Everytime central heating system fires up it sounds like I have my own personal generator in the house any ideas what this could be please. It only lasts a few minutes but happens each time.

thanks

[stoneyboy]

jayjay,
Start by listening to the circulating pump - there may be a partial airlock which is allowing the pump to free-wheel.
end