What is already included
A wireless room thermostat comes with every installation on this site, paired and set up at handover. For plenty of households that is the right level: set the temperature, let the boiler do its job.
What a smart thermostat adds
Control from your phone, schedules that follow your week rather than a dial, and visibility of what the heating is actually doing. If you are out at irregular hours or simply like a warm house waiting without heating an empty one, that control is the point.
Why install day is the moment
The wiring, pairing and commissioning are already happening — adding a smart control while the engineer is at the boiler is tidier and cheaper than a separate visit later. Mention it when you book the survey and it goes into the written quote as an itemised line, so you can take it or leave it with the real number in front of you.
If you already have one
Bring it up at the survey — compatibility with the new boiler is checked there, and where your existing smart control can carry over, it does. Synergy also fits smart thermostats as a standalone job — see the smart thermostats page on synergygas.org.