Thermostat Not Working? Quick Checks Before You Call an Engineer
Before booking a call-out, these are the checks worth thirty seconds of your time.
Before assuming it's a boiler fault, it's worth ruling out the thermostat itself — a surprising number of "no heating" calls turn out to be exactly this.
Checks worth trying first
Batteries — wireless thermostats run flat more often than people expect, and the display can still show numbers while failing to actually communicate with the boiler.
Signal — check the display isn't showing a "no signal" or connection error.
Schedule — confirm the schedule hasn't reverted to a default or summer programme, particularly after a power cut.
Smart thermostats — check the app for a connectivity warning.
When it's a wiring or boiler-side fault
If the thermostat display works normally, is calling for heat, and the boiler still doesn't respond, the fault is more likely in the boiler's controls or wiring centre — that's when it's worth calling us rather than continuing to troubleshoot yourself.