I have a potterton kingfisher floor standing boiler,which carries about 18 rads the rads on the top floor will not get hot. I have tried turning off the rads at the bottom , and leaving the top ones on, I have bleed them for three day. I have check the tanks, the top rads only get hot at the bottom of the rads.

Derek, January 2011

I'll assume the F&E cistern is above the level of the top rads.
If you bleed them and air comes out until they are full, then they refill with air a day or so later, you have a problem with air being sucked into the system, the configuration of the pump/cold feed/open vent need to be corrected.

OR:
If they won't bleed or fill, the cold feed from the F&E is blocked and will need to be cleared (messy job).

Carefree, January 2011