I have a vailant combi boiler.   When the heating is on and the boiler fired up heating the water for the radiators and I turn the tap on there is hot running water.   When the boiler is not fired up for the heating i.e. the radiators are at temperature and I turn the tap on the boiler isn't firing up to heat the water.   I've switched the heating off to tap only and still its not heating the water.   The water pressure guage is at 1.5 as it should be.   I live in a hard water area.   Any help or advice muchly appreciated so I don't get ripped off when I call the plumber.                                                                                                                                                                             

Sounds like the change over valve....... A  valve that switches from heating to hot water when required.... had one go on my boiler a few years ago.... but be warned not a particularly cheap fix............... but cheaper than a new boiler.                                                                                                                                                                             

oooooooo soz bb. i can't help you this time. welcome to the site anyway!                                                                                                                                                                             

kick it or hit it thats my only idea to help, sorry its not much                                                                                                                                                                              

Might be awkward kicking it if it's mounted high.........                                                                                                                                                                              

would need a pair of kinkey boots for that rube !!!!!!!!                                                                                                                                                                             

Oh god you women have one track minds..                                                                                                                                                                              

nah rube its your mind those boots have a huge heel for more heinght, and they have a platform too plus they tight so give calf muscle some support !!!!!!!!!!!!!                                                                                                                                                                             

.........{DROOL}...........