Thermostat shows very slow response; rooms overshoot set temperature by several degrees

Safety: Only configuration and relocation are involved.

Steps:

• Check thermostat location: it should be on an internal wall, about 1.5 m above floor level, away from direct sunlight, radiators, and external doors.
• In the installer menu, ensure the control mode is set to modulating (eBus/OpenTherm) if supported by your Glow‑worm boiler, rather than simple on/off.
• Enable optimisation features such as load compensation, weather compensation (if outdoor sensor fitted), and optimum start/stop if available.
• After changes, monitor room temperature over several days and fine‑tune any available control parameters (cycle rate, hysteresis) according to the manual.

Remedy:

• If overshoot persists despite correct setup and location, consult a heating engineer to check boiler sizing and system balancing.