Introduction
If your boiler in Lindford (GU35) starts to ignite but then quickly cuts out, it could be a sign of a faulty flame sensor. This small component plays a critical role in ensuring your heating system runs safely and efficiently. In this guide, we’ll cover why flame sensors fail, how to identify the warning signs, and what steps you can take before calling in a Gas Safe engineer. Whether you’re based in Lindford, Bordon, Alton or nearby Farnham and Liphook, this advice will help you keep your boiler firing reliably through the colder months.
What Causes Your Boiler to Ignite and Then Cut Out?
The Role of a Flame Sensor
A flame sensor, also known as a flame detection electrode, verifies that a flame is present once the gas valve opens. If the sensor does not detect a flame, it sends a signal to the boiler’s control board to shut off the gas supply, preventing unburnt gas from building up inside the combustion chamber.
Common Flame Sensor Faults
- Dirty or corroded sensor tip: Soot and debris accumulate over time, insulating the sensor and stopping it from reading the flame.
- Electrical faults: A damaged wiring loom or loose connector can interrupt the sensor’s electrical circuit.
- Worn electrode: The sensor tip can degrade after years of constant heating cycles.
- PCB issues: In rare cases, the boiler’s control board malfunctions and cannot interpret the sensor signal correctly.
Signs of a Faulty Flame Sensor
Besides the boiler cutting out shortly after ignition, look out for these symptoms:
- Repeated ignition attempts followed by a lockout condition.
- Regular fault codes flashing on the display (refer to your boiler manual for code details).
- A smell of gas around the boiler—if you detect this, shut off the appliance and ventilate the area immediately.
- Unusual clicking noises as the boiler attempts to relight.
Troubleshooting Steps You Can Try
Before you dial for boiler repair, you can perform these basic checks. Always prioritise safety: if you’re unsure, stop and call a professional.
- Reset the boiler: Turn off the power for a minute and restart. This can clear minor electronic glitches.
- Inspect for error codes: Consult your user manual to decode any fault codes and follow the suggested actions.
- Look for loose connections: Check that all wiring to the flame sensor is securely clipped in—power down the boiler first.
- Clean the sensor tip: If you’re confident, remove and gently clean the electrode with fine-grade steel wool to remove soot.
- Check gas pressure: Low mains gas pressure in GU35 areas like Lindford, Bordon or Alton could result in weak flames that the sensor fails to detect.
When to Call a Gas Safe Engineer
If the boiler still cuts out after your checks, it’s time to call a qualified Gas Safe engineer. Flame sensor replacement and testing require specialist tools and certification. Our local team in Lindford, Alton and Liphook can diagnose the issue swiftly and carry out any necessary repairs, ensuring your heating breakdown doesn’t leave you in the cold.
Preventative Maintenance
Regular servicing is key to preventing flame sensor faults and other boiler issues. We recommend an annual service to maintain efficiency and prolong the life of your heating system. Book your next boiler servicing appointment today.
- Clean or replace air filters on combi boilers to reduce debris reaching the sensor.
- Flush radiators to prevent sludge buildup affecting system pressure and flame stability.
- Check condensate pipe for blockages that could cause lockdowns in winter.
- Verify thermostat operation to ensure accurate temperature control.
Upgrading Your Boiler System
If your boiler is over 10 years old and you’re facing repeated faults, a new unit could save you money in the long run. Consider a high-efficiency condensing boiler with improved flame detection technology. Contact us for new boiler installation and explore our range of boiler cover options to protect your investment.
Frequently Asked Questions
Q: How often should a flame sensor be replaced?
A: Flame sensors can last up to 15 years, but if you experience ignition cut-outs, replacing it during a service is a cost-effective fix.
Q: Can I clean the flame sensor myself?
A: Yes, if you’re skilled with basic DIY. Always isolate power and gas before removing the sensor tip, then use fine-grade steel wool to clean gently.
Q: Will a faulty flame sensor affect my gas bills?
A: Inefficient combustion or repeated ignition attempts can drive up energy consumption. Keeping the sensor in good condition helps maintain efficiency.
Q: What safety checks should I perform after replacing the sensor?
A: Ensure all connections are tight, reassemble the boiler correctly, and run through a heating cycle to check for stable flame and normal operation.
If you need help with your flame sensor or any other boiler issue, our local engineers are here to help. Call us on (01420) 558993 or book online at embassygas.com/book.
Written by Embassy Gas — your local heating experts covering Lindford, Bordon, Alton, Farnham and surrounding areas.