Ok heres my problem I recently had to drain my central heating system to replace a leaking rad, I have refilled the system added inhibitor fully bled all the rads and all was fine as before but I am now getting a loud gurgling noise from the small copper header tank when the central heating is turned off.Also when the heating comes on in the morning from being off all night I am getting warm water coming out of the header tank overflow outside??? anyone got any idea what this could be??
