BoilerTroubleshooting2026-02-26
Boiler Keeps Turning Off: Causes
Frequent shutdowns point to low pressure, overheating, a sensor fault or a blocked condensate.
A boiler that keeps shutting down is protecting itself from a fault. Here's what triggers it.
Common triggers
Low pressure, overheating from poor circulation, a dirty flame sensor, a faulty thermistor, or a blocked condensate pipe all cause repeated shutdowns.
What to do
Check pressure (1–1.5 bar) and top up if low; in cold weather check the condensate pipe; persistent shutdowns need a technician.
Key takeaways
- Check and top up pressure
- Check the condensate pipe in winter
- Note any error code
- Repeated shutdowns need service
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