Troubleshooting
Radiators Stay Hot When Heating Is Off
Heat where you didn't ask for it points to a valve issue.
If your radiators get warm even when the heating is off — for example, only the hot water should be running — the most likely cause is a diverter valve that isn't sealing, allowing heated water to leak into the heating circuit. Occasionally it's a gravity-circulation effect or a control fault.
Diverter valve work is internal, licensed repair.
Common causes
- Diverter (3-way) valve not sealing
- Faulty valve actuator
- Control/PCB calling for heat incorrectly
- Gravity circulation in the system
This is not a DIY repair
Combi boilers are gas-fired appliances regulated under the BC Safety Standards Act. Opening the unit, touching the gas valve, or working on the flue without a valid BC gas-fitter licence is both unsafe and illegal. Diagnosing the fault is helpful — fixing it should always be left to a certified technician.
Call 778-909-5731Related symptoms & help
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