top of page

Why Has My Boiler Stopped Working This Winter? Common Faults and DIY Fixes for UK Households

As the winter chill sets in, the last thing any UK household wants is a malfunctioning boiler. It's a scenario that can leave you shivering and frustrated. Before you reach for the phone to call a professional, let's explore some common boiler faults that may be behind the issue and, more importantly, how you can tackle them yourself.

  1. Frozen Condensing Pipe: One of the most common issues during winter is a frozen condensing pipe. The condensing pipe, responsible for transporting condensate away from your boiler, can freeze in extremely cold temperatures, causing a blockage. DIY Fix: Thawing a frozen condensing pipe is a relatively simple task. Gently pour warm (not boiling) water over the pipe or use a hot water bottle to defrost it. You can also wrap the pipe with towels or cloths soaked in warm water to speed up the process.

  2. Low Boiler Pressure: Low boiler pressure is another frequent culprit, leading to a loss of heating or hot water. The pressure gauge on your boiler should typically read between 1 and 1.5 bars. DIY Fix: To increase the pressure, locate the filling loop (usually a flexible hose connecting the boiler to the mains) and slowly turn the valve until the pressure gauge reaches the desired level. Be cautious not to over-pressurise, as this can cause other issues.

  3. Faulty Thermostat: A malfunctioning thermostat can misread the temperature, leading to your boiler not firing up when it's supposed to. DIY Fix: Check if the thermostat is set to the desired temperature. Replace the batteries if it's a wireless thermostat, and ensure there are no obstructions affecting its accuracy. If problems persist, it might be time to consider a thermostat replacement.

  4. Air in the Radiators: If your radiators feel cold at the top, there may be air trapped inside the system, preventing effective heating. DIY Fix: Bleeding the radiators is the solution here. Use a radiator key to open the bleed valve slightly until you hear a hissing sound, indicating the release of trapped air. Once water starts to dribble out, close the valve.

  5. Faulty Pilot Light or Ignition: If your boiler's pilot light has gone out or the ignition system is faulty, the boiler won't start. DIY Fix: Follow your boiler's manual to relight the pilot light. If the pilot light won't stay lit or the ignition system is problematic, it's advisable to contact a professional for further assistance.


While some boiler issues require professional attention, many common faults can be resolved with a bit of DIY effort. Regular boiler maintenance and addressing problems promptly can ensure a warm and cosy winter for your household. If in doubt or if problems persist, don't hesitate to consult a qualified heating engineer to ensure your boiler operates efficiently throughout the colder months. Stay warm and enjoy a hassle-free winter!

If your boiler is older, did you know you can likely qualify for help replacing it through various Government backed initiatives? Check if you are eligible here.


bottom of page