Glow-worm F15 Fault Code Guide for Homeowners: Meaning, Symptoms, Actions, Costs, Causes, Prevention

Meaning of the Glow-worm F15 Fault

The Glow-worm F15 fault indicates an issue with the return thermistor. The return thermistor measures the temperature of water returning to the boiler. When the thermistor malfunctions, it sends wrong temperatures to the boiler’s controls.

What is the return thermistor?

The return thermistor is a temperature sensor located on the return pipe of the boiler. It monitors the temperature of the water returning from the heating system. Accurate readings ensure the boiler operates efficiently.

How does the return thermistor affect boiler performance?

The return thermistor affects boiler performance by providing temperature data. The boiler uses this data to regulate heating cycles. Incorrect data from a faulty thermistor can disrupt heating efficiency and cause the F15 fault code.

Why does a return thermistor fail?

A return thermistor fails due to several reasons. Common causes include age, wear and tear, electrical faults, and exposure to extreme temperatures. Regular maintenance can help identify potential issues early.

How is the return thermistor replaced?

Replacing the return thermistor involves accessing the boiler’s internal components. A Gas-Safe engineer disconnects the faulty thermistor, installs a new one, and ensures proper wiring. The boiler is then tested for correct operation.

Symptoms of the Glow-worm F15 Fault

The Glow-worm F15 fault has several noticeable symptoms. You may experience a lack of hot water or ineffective heating. The boiler may display the F15 fault code on its digital screen.

You might hear unusual noises from the boiler. These noises can indicate issues with the return thermistor. The boiler may cycle on and off frequently, trying to correct the error.

How To Recognise The F15 Fault on Different Types of Glow-worm Boiler

Glow-worm Combi Boilers

On Glow-worm Combi boilers, the F15 fault code appears on the digital display. The boiler may stop producing hot water. Heating performance may drop significantly.

Glow-worm System Boilers

Glow-worm System boilers also show the F15 fault code on the display. Heating issues can arise, with radiators not warming up properly. The hot water supply may become inconsistent.

Older Non-Digital Glow-worm Boilers

Older non-digital Glow-worm boilers do not show a fault code. Instead, you may notice a lack of hot water and ineffective heating. Frequent boiler cycling and unusual noises can also indicate the F15 fault.

Cost to Repair F15 Fault on Glow-worm Boilers

Repairing the F15 fault on Glow-worm boilers involves varying costs. The minimum cost to repair the F15 fault is typically around £100. This covers basic labour and minor parts replacement.

The maximum cost can reach up to £300. This includes extensive repairs or replacement of major components. Most repairs for the F15 fault cost between £150 and £200.

Costs depend on the complexity of the repair. Labour charges and parts prices influence the total expense. Always use a qualified Gas-Safe engineer to ensure safe and proper repairs.

What to Do When Your Glow-Worm Boiler Shows the F15 Fault

When your Glow-worm boiler shows the F15 fault, you should take immediate action. First, turn the boiler off to prevent further issues. Next, check the instruction manual for any specific guidance related to the F15 fault.

Ensure the area around the boiler is safe. Look for any signs of gas or water leaks. If you detect any leaks, shut off the gas supply and water valves immediately. Contact a Gas-Safe engineer for professional assistance.

How to Turn Off the Boiler Safely?

Turn off the boiler by switching off the power supply. This prevents the boiler from attempting to operate while the fault persists. Refer to your boiler’s instruction manual for the exact location of the power switch.

Should I Shut Off the Gas Supply?

If you suspect a gas leak, shut off the gas supply immediately. Locate the gas valve, usually found near the boiler. Turn the valve to the off position to stop the gas flow.

Where to Check for Water Leaks?

Check around the base of the boiler and nearby pipes. Look for signs of water pooling or dripping. If you find a leak, turn off the water supply and contact a Gas-Safe engineer.

How to Contact a Gas-Safe Engineer?

Contact a Gas-Safe engineer through their official website or phone directory. Make sure they are registered and qualified to handle boiler repairs. Avoid attempting any repairs yourself to ensure safety.

Always follow the instruction manual for your boiler. Use a Gas-Safe engineer for any further work to ensure safety and compliance. The next section will describe the major causes of the fault in more detail.

The 3 Major Causes of The F15 Fault

Three key reasons trigger the Glow-worm F15 fault. These include a faulty return thermistor, wiring issues, and problems with the boiler’s PCB. Understanding these causes helps in diagnosing and addressing the fault effectively.

Faulty Return Thermistor

A faulty return thermistor is the most common cause of the F15 fault. The thermistor measures the temperature of the water returning to the boiler. If it fails, it sends incorrect readings, causing the boiler to malfunction. Age, wear, and exposure to extreme temperatures can damage the thermistor.

Wiring Issues

Wiring issues can also lead to the F15 fault. Damaged or loose wires can interrupt the connection between the thermistor and the boiler’s control system. This disruption causes incorrect temperature readings. Regular inspections can help identify and fix wiring problems before they cause faults.

Problems with the PCB

The boiler’s PCB (Printed Circuit Board) controls its operations. A malfunctioning PCB can cause various errors, including the F15 fault. PCB issues can arise from electrical surges, water damage, or general wear and tear. Replacing or repairing the PCB typically requires a Gas-Safe engineer.

By understanding these causes, you can better diagnose and address the F15 fault. The next section will discuss preventative measures in more detail.

Preventing Future F15 Faults

Preventing future F15 faults involves regular maintenance. Annual boiler maintenance is essential to assure all components work correctly. A boiler service contract offers peace of mind, covering routine checks and repairs.

During maintenance, a Gas-Safe engineer inspects the return thermistor and wiring. They check for wear and tear, replacing parts as needed. Regular servicing helps find potential issues. It finds them before they cause faults. This keeps your boiler efficient.

Disclaimer

Work beyond the manual’s operations must be done by a Gas-Safe engineer. Attempting repairs yourself can be dangerous and may void warranties. Always ensure a qualified professional handles all boiler repairs. This is to ensure safety and compliance.