At first I couldn’t pair this with the control in the boiler no matter how many times I followed the instructions in the booklet. So I looked on the Salus website for help and they had a video showing how to do it, the video shows a different key combination to the one in the instruction book to put the thermostat into pairing mode. Once I followed the instructions on the video everything paired up and the system is working well. The app is great compared to having to program or control the thermostat manually. Would definitely recommend, just make sure you watch the video from the salus website!