I am finding it increasingly difficult to turn off the hot tap on my mixer tap. ( It is a metal one with two taps.)The cold tap is easy to turn off. Can you suggest why and what can I do to put this right. i am worried i might soon be unable to turn the hot tap off.

worried, May 2010

remove the tap insert give it clean re silicone grease good as new.

hi-spec plumbing & heating (essex), May 2010