PanicStation.org
UK USA
uk Home & property emergencies heating stuck on • boiler wont turn off • radiators stuck on • house overheating • indoor temperature too high • thermostat not working • heating timer stuck • programmer not responding • smart thermostat failed • trv valve stuck open • heating relay stuck • boiler keeps firing • central heating runaway • electric heater stuck on • storage heater overheating • communal heating stuck on • too hot to sleep indoors • heat exhaustion indoors • carbon monoxide alarm concern • rented flat heating emergency • landlord repair urgent • vulnerable person overheating

What to do if…
your heating is stuck on and the indoor temperature is rising beyond what feels safe

Short answer

Stop the heat source first: turn heating controls to OFF, then isolate power to the heating system (for many homes, this is the boiler’s fused spur/isolation switch) if heat keeps running. While you do that, cool one room and move people/pets there.

Do not do these things

  • Do not rely on opening windows alone while the system keeps heating — ventilate and shut the heat source down if you can.
  • Do not remove boiler covers or work on wiring/valves if you’re not trained.
  • Do not ignore a carbon monoxide (CO) alarm or symptoms like headache, dizziness, nausea, confusion, or collapse — treat as urgent.
  • Do not leave babies, older adults, or pets in the hottest rooms while you troubleshoot.

What to do now

  1. Move everyone (and pets) to the coolest available space (often a shaded, lower-floor room). Cool it fast: close curtains/blinds on sunny windows, open windows on opposite sides (if safe), and use a fan if you have one.
  2. Try the “normal off” controls (quick wins):
    • Set the thermostat very low and set mode to OFF.
    • Check any timer/programmer/smart thermostat/app and set heating to OFF (not “auto”).
    • Turn radiator TRVs fully down/off in rooms you don’t need (keep the “cool room” as cool as possible).
  3. If it’s still heating, isolate the heating system safely:
    • Boiler-based heating: switch the boiler/heating system OFF at the fused spur/isolation switch (often near the boiler, sometimes with a red light), or use the boiler’s own power button if it’s clear.
    • Electric room heaters/storage heaters: switch the heater OFF at the wall switch/isolator (or the clearly labelled breaker for that heater circuit). Keep combustibles (clothes/curtains/bedding) away from hot surfaces.
    • Communal/district heating: you may not be able to fully “turn it off” yourself — turn TRVs down/off, close zone controls if you have them, and contact the building’s concierge/management/emergency repairs line.
    • Consumer unit: only switch off a circuit if it’s clearly labelled and you’re confident. If you’re not sure, stop here and get help.
  4. If a CO alarm sounds or you suspect CO: get everyone into fresh air immediately (outside if possible), open doors/windows on your way out, then call the appropriate gas emergency number:
    • Great Britain: National Gas Emergency Service 0800 111 999
    • Northern Ireland: Northern Ireland Gas Emergency Service 0800 002 001 If anyone is severely unwell, call 999.
  5. If anyone seems heat-unwell, cool them now:
    • Move to a cooler place, loosen clothing, give cool water in small sips if fully alert, and cool skin with cool water/damp cloths.
    • If signs suggest heatstroke (confusion, very hot skin, collapse, seizure, not improving), call 999 and keep cooling while waiting.
  6. Get the right property help:
    • If you rent: report an urgent repair to your landlord/letting agent/council housing repairs (use the out-of-hours number if needed). Tell them you’ve isolated the heating power (or can’t, if communal).
    • If you own: contact a Gas Safe registered engineer for gas appliances (or a qualified heating/electrical engineer for electric/communal systems). Say: “heating stuck on / won’t turn off; indoor temperature rising; power isolated where possible.”

What can wait

  • You do not need to diagnose whether it’s the thermostat, programmer, motorised valve, wiring fault, or boiler control board.
  • You do not need to decide on parts, quotes, or replacements until the home is cooling and everyone is safe.
  • You do not need to bleed radiators or adjust boiler pressure as a first step for “stuck on” heating.

Important reassurance

It’s normal to feel panicky when your home won’t stop heating. Once you’ve stopped the heat source and made a cooler room, you’ve removed most of the immediate risk and bought time to get repairs arranged.

Scope note

This is first-steps-only guidance to stabilise overheating and shut the system down safely. Fault-finding and repairs should be done by qualified professionals, especially for gas appliances.

Important note

This is general safety information, not a substitute for professional advice. If you suspect carbon monoxide or anyone is seriously unwell from heat, treat it as an emergency and call the appropriate emergency services.

Additional Resources
Support us