When to Shut Off Your Boiler
Sometimes the safest move is to switch the boiler off and call for help. Here are the situations where you should shut it down immediately.
A boiler is built to shut itself down when it senses trouble, but there are times you should not wait for it to decide — you should switch it off yourself. Knowing these situations, and where your shut-offs are, turns a scary moment into a managed one.
Shut it off immediately if you notice
- A gas smell (after leaving, if safe — see our gas-leak guide).
- Water leaking onto electrical components or pooling under the boiler.
- A burning or hot-electrical smell, smoke, or scorching around the unit.
- A relief valve actively discharging hot water or steam.
- A carbon monoxide alarm sounding.
How to shut it down
Most boilers can be switched off at the unit’s power switch or the fused spur/breaker that feeds it. For a gas concern, the gas can be turned off at the appliance isolation valve or the meter. Knowing where these are before an emergency is worth a five-minute walk-through with your technician.
After shutting down
Ventilate if there was any gas or combustion concern, keep the area clear, and call a licensed technician — or emergency services and FortisBC for a gas or CO emergency. Do not restart the boiler until the cause has been found and fixed.
Key takeaways
- Shut the boiler off for leaks onto electrics, burning smells, an actively discharging relief valve, or a CO alarm.
- Know where your boiler power switch and gas isolation valve are before you need them.
- Do not restart until a licensed technician has diagnosed the cause.
Frequently asked questions
Where is the shut-off for my boiler?
There are usually two: an electrical switch or breaker that powers the boiler, and a gas isolation valve near the unit (plus the main gas meter). Ask your technician to point both out during a service so you are ready in an emergency.
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