Boiler Not Firing Up? - TM Hughes & Son

If your Boiler isn’t firing up, it can be frustrating and inconvenient, especially in cold weather. Common causes include:

Error codes indicating specific faults
Power supply issues
Incorrect thermostat settings
Lack of gas supply
Faulty pilot light
Low pressure
A frozen condensate pipe,
Incorrect timer settings
A blocked flue
Air trapped in the system

You can often identify and resolve the problem by systematically checking each area. However, for complex issues or if you’re not confident in your ability, it’s always best to seek professional help.

Common Issues & Troubleshooting Steps

If your Boiler isn’t firing up, it’s probably one of ten common issues. Understanding and troubleshooting these problems will help you get your heating system back up and running.

We will guide you through the ten common issues and their respective troubleshooting steps to help you diagnose and fix them yourself.

Error Codes & Diagnostics

Check your Boiler to see if it’s displaying an error code. Refer to your Boiler’s manual to understand what each code means. Common issues include ignition failures, pressure problems, or blocked vents. Once you’ve identified the error code, follow the recommended troubleshooting steps. Sometimes, resetting the Boiler can resolve the issue. However, if the error persists or you’re unsure how to fix it, it’s best to call a professional Boiler engineer.

Power Supply Issues

When your Boiler isn’t firing up, the first thing to check is the power supply. Ensure the power switch to the Boiler is turned on. Inspect the Boiler RCD fuse in your fuse box. A tripped breaker will cut power to the Boiler. Resetting the breaker might restore power. Sometimes, the issue could be with the electrical outlet or the wiring, requiring a more thorough inspection by an engineer.

Thermostat Settings

The thermostat controls when your Boiler turns on and off. Start by verifying it’s set to a temperature higher than the current room temperature. This simple step ensures the Boiler receives the signal to start. Check the thermostat batteries (if it’s not a wired-in thermostat). Low or dead batteries can cause the thermostat to malfunction. Replace them if necessary. Also, ensure the thermostat is not exposed to direct sunlight or heat sources, which can cause incorrect readings. Proper thermostat settings are essential for your Boiler to run efficiently and maintain a comfortable indoor temperature.

Gas Supply Problems

A steady gas supply is vital for your Boiler to function. Ensure the gas valve supplying your home is open. Sometimes, gas supply issues can be caused by external factors such as utility work in your area. If you suspect a gas leak, it’s essential to address it immediately by turning off the gas supply and contacting a gas engineer. Never attempt to fix gas leaks yourself.

Pilot Light Issues

Locate the pilot light and see if it’s burning. If it’s out, follow the manufacturer’s instructions to relight it. If the pilot light keeps going out, the thermocouple may be faulty. The thermocouple is a safety device that stops gas leaking if the pilot light goes out. Replacement of the thermocouple will get your Boiler back up and running. This is a professional job that a qualified gas engineer must undertake.

Pressure Levels

Boiler pressure is a key factor in its performance. Check the pressure gauge, which typically should be 1.5 bars (or between 1 and 2 bars. Consult your Boiler manual for exact pressure). If the pressure is too low, your Boiler might not fire up. You’ll need to add water to the system using the filling loop to increase the pressure. Follow the manufacturer’s instructions to avoid over-pressurising. If the pressure drops frequently, a leak or an issue with a pressure relief valve might occur. Book an inspection with a Boiler engineer.

Condensate Pipe Freezing

The condensate pipe can freeze in winter, causing your Boiler to shut down. The condensate pipe carries away acidic water produced during the Boiler’s operation. The blockage triggers a safety mechanism when it freezes, preventing the Boiler from firing. Look for water dripping or a gurgling sound to identify a frozen pipe. Thaw the pipe by pouring warm (not boiling) water or using a hot water bottle. Once thawed, reset your Boiler. Insulating the condensate pipe will help prevent freezing in the future, ensuring your Boiler runs smoothly during cold weather.

Timer/Programmer Settings

Incorrect timer or programmer settings can prevent your Boiler from firing up when needed. Ensure the timer is set to the correct time and the Boiler is programmed to operate when you need heating or hot water. Sometimes, a simple setting mistake can cause the Boiler to remain off. Check if the timer is set to a different schedule or accidentally switched to manual mode. Correcting these settings is straightforward but essential for ensuring your Boiler operates according to your daily routine and provides consistent heating and hot water.

Blocked Flue

A blocked flue can prevent your Boiler from firing by obstructing the ventilation needed for safe operation. Flames can become blocked by debris, nests, or even snow. Check the flue for any visible obstructions, but avoid tampering with it directly, as it can be dangerous. A Gas Safe registered engineer can inspect and clear the blockage safely. Annual Boiler servicing is essential to prevent blockages. Ensuring the flu is clear allows your Boiler to vent properly, maintains efficiency, and prevents dangerous gases from accumulating in your home.

Air In The System

Trapped air in your heating system can cause your Boiler to malfunction. The system’s air signs include cold spots on radiators or unusual noises. Bleeding your radiators can release the trapped air. To do this, turn off the heating, use a radiator key to open the valve slightly, and let the air escape until water starts to flow. Close the valve and check the Boiler pressure, topping it up if necessary. Regularly bleeding your radiators ensures the heating system operates efficiently and prevents strain on the Boiler, helping to maintain consistent heating throughout your home.

Need Help?

If you have tried the above procedures and your Boiler still doesn’t work, you’ll need professional help.

If you’re an Essex resident, one of our experienced Gas Safe Registered engineers can help. Please contact us for advice or to book a visit. We provide same-day service with no call-out charges for repairs.