Room thermostat wiring faults and why heating won't switch off

What we check first with room thermostat wiring faults

Heating that runs continuously regardless of the dial usually means the thermostat's switching contact is stuck closed or has been wired to permanently bridge the demand circuit. Heating that never fires despite an obviously satisfied call points to a broken link, a dead battery in a wireless receiver, or a stat wired to the wrong terminals entirely. Replacement stats occasionally need the wiring centre terminals checked against the manufacturer's diagram rather than simply matched by wire colour.

Room thermostat wiring faults — the facts that change the job

• Continuous heating regardless of setting suggests a stuck stat contact
• Wireless thermostats fail silently when the receiver or stat battery runs flat
• Wire colours are not standardised across every thermostat brand
• A loose terminal at the wiring centre can cause intermittent operation
• Smart thermostat retrofits sometimes need an added common wire

Questions we get asked

Can I fit a new thermostat myself?

Basic like-for-like swaps are within many homeowners' ability, but anything involving the wiring centre or smart control retrofit is safer left to an engineer.

Why does my heating fire a while after I turn the thermostat up?

Some delay is normal with certain boiler cycling logic, but a long or inconsistent delay can point to a weak wireless signal or a failing receiver.

Where we deal with this

• Doulting (BA4) · 6 mi
• Walton (BA16) · 14 mi
• Keynsham (BS31) · 9 mi