Drayton rf1 wireless system problem?

Recently moved home. I have followed all the Q&As on this site regarding the rf1 system in my new home. I put new batteries into the thermostat box and reconfigured it to the receiver on the wall. However I am still not getting central heating. I am getting hot water so the boiler is working but it almost seems as if the receiver is not talking to the boiler to tell it to come on. Help needed urgently as only just paid £100 to have the boiler serviced which took only 15 minutes and so loath to pay any more.