To add hot water control to a system that already uses a KL08RF wiring centre, a UG600 gateway and SQ610RF thermostats, a common approach is to use an SR600 smart relay wired to your hot water motorised zone valve — wired so that when the relay is ON, the zone valve opens.

In the app, set up an On/Off schedule on the SR600 to define the timer periods when the water needs heating.