no hot water but hot rads?

Summon the services of an engineer.

Your boiler will have a hot water storage tank and close to it will probably be an electrically operated control valve that directs the heated water to the tank or the rads as required - your valve may be stuck in the radiator position.

When the engineer arrives stress to him that you will want him to diagnose and repair your boiler rather than guess which part is broken and change pieces one at a time at your expense (some of them do this) until he solves the problem.

In the mean time you can heat the water in the tank with the immersion heater if you have one.

Having insulted all boiler engineers I now admit that I too am just guessing - but the difference is I'm not costing you anything.

Good luck...

By the way - Your old Kingfisher 2 boiler is not very efficient (about 65%) and last made in 1998 as far as I can tell.

Peccavi
April 2009