Worcester Greenstar thermostat? issue

Hi

Im wondering if anyone can point us in the right direction. It seems the thermostat isnt working - its in our living room and the boiler in the kitchen. The boiler was installed 5 years ago and then the company put a blanking plate over where the thermostat was in the kitchen and put a Honeywell battery thermostat in the front room.

There is a white box in the airing cupboard and a switch on it which if pressed makes the heating come on. The boiler fires up and heats the rads.

So im not sure if i should just try and replace the living room thermostat or add a wired one in the kitchen where it used to be. Im told its not that simple as the wireless stat signals to the box in the airing cupboard and not to the boiler itself. So i need to "pair" a new wireless stat with the boiler,or that i might need a new box in the airing cupboard too, but i thought if i just reconnect a wired one, that should sort it and theyre cheaper than the battery ones ive seen

Any ideas on the best way to sort this?

thanks

Garry