ideal icos he18

Hi all. I've done some digging around the web and on the forum and can see others have succeeded in reconnecting / pairing the thermostat with the receiver using the hive instructions here as the models are similar via a previous thread...

My Honeywell room thermostat is wall mounted and wireless and on occasion if I wish to over-ride or boost the central heating outside of the normal settings the signal doesn't always seem to be picked up by the boiler. Is the 'receiver' within the boiler? Neither I nor my plumber or electrician...