Easy Fixes for Boilers

A well functioning boiler is the life-blood of any home. Be prepared to fix minor issues before calling a heating specialist to ensure your home stays warm and cozy. 

Ensure that the power is on and the settings are correct

Run through this checklist of fixes before calling the emergency heating engineer.

• Are the boiler and its controls receiving power? The boiler is often on a separate electrical circuit, so check its circuit breaker or fuse if it won't fire up but the power is on elsewhere in the house.
• Is the programmer working? Can you see the digital display, if it has one, or any on/off lights?
• Turn up your room thermostat(s) — the boiler won't fire up if heat is not needed.
• Does the boiler have fuel? If your home runs on oil or bottled or bulk gas, check that you haven't run out.
• Is the pilot light still lit? If it has blown out, follow the boiler instructions to relight it.
• If you have a condensing boiler, check that the condensate pipe hasn't frozen as this will cause the boiler to shut down (see below).

If your home has multiple room thermostats, each controlling a zone of the house, your system is probably fitted with zone valves. These valves — square boxes attached to pipes near your boiler — regulate the flow of hot water to the various zones in your home and can sometimes get stuck in a closed position. If they won't operate, the boiler may not fire up. They usually have a lever for manual operation so try moving it and seeing if the boiler starts. Call a professional to check and replace the faulty valve.

Thaw the condensate pipe

Condensing boilers are a highly efficient way of heating your home and producing hot water. They extract energy directly from burning fuel, but also by condensing the steam created during combustion. As this steam condenses, water must be removed via a drain tube — the condensate pipe — to the outdoors. Unfortunately, the design of the boiler makes this tube vulnerable to the cold; if it freezes, the boiler will shut down.

• If the boiler has a digital display, it may be showing a fault code or a warning light might be illuminated. Double-check the instruction manual to see if this indicates a freeze.
• Is there a gurgling sound coming from the boiler or the condensate pipe? That's a good indication that the pipe is frozen up.
• The pipe is most likely to be frozen at the end where it runs into the drain, or perhaps where it turns a corner — you should be able to feel the frozen section with your hand.
• To defrost the pipe, pour hot, but not boiling, water over it until the ice blockage has thawed.
• To stop the pipe from freezing in the future, wrap the pipe with burlap, old towels, bubble wrap or foam pipe insulation.