Radiators working intermittently.

I live in a three storey house and have a boiler mate OV A class, the radiators are controlled via a wall mounted thermostat on the first floor and by radiator mounted valve thermostats on the ground and second floors.
When the heating is on constant the radiators on the ground and second floors are working but the radiators on the first floor which are controlled by the wall thermostat are not working.
I am baffled could someone advise me what the problem could be.

Many thanks

Will

I presume they did work?
Have you bleed the rads?
Your heating system may be zoned.
But you could try.
Turn off all the rads which do work and then see what happens.
It would not be to hard to locate the problem if on site.
When did you last have your boiler serviced?
Mike
MGC/H2O
Norfolk