I read on the Glow Worm site that the Ultracom 38 CXi can have an outside sensor. I think this means for outside weather compensation. The installation manual mentions little of this and does not show how to connect one. Does anyone know of this sensor? I also want a remote timer. May the boiler facia mounted timer be move to another room? What do people think of the Ultracom 38 CXi? It looks like a Vaillant inside and they own Glow Worm. Thanks.