Cold Weather Advice

Contact us if you have urgent problems because of the cold weather.

No Heating? Your boilers condensate pipe could be frozen

Frozen boiler condensate pipes are a common problem during cold weather. The water in the pipe freezes and causes a blockage which makes your boiler cut out. If yours is frozen and your heating or hot water is affected, you can try to thaw it out yourself. 

To check if your boiler has a condensate pipe, look underneath where there are lots of pipes connected. If one of the pipes is plastic (usually white and about 2cm in diameter) and the rest are metal, this is probably the condensate pipe. Find where the pipe goes outside of your home. It should run into a drain.

Thawing and clearing the pipe yourself

There are two ways you can try to thaw the pipe and clear the ice blockage. If you don't feel confident doing this, just get in touch and we'll get an engineer to come out and fix the problem. 

Method 1: Pour hot (not boiling) water onto the frozen pipe

This involves pouring hot water over the frozen area of the pipe. Do not use boiling water for this and take care whilst using any hot water. Heat the water using a kettle or a microwave if your boiler has stopped working. Find the part of the pipe that is frozen and gently pour the hot water over the area. Pour the water using a kettle, jug or watering can.

Method 2: Place a hot water bottle or wrap on the frozen pipe

The second option is to use either a hot water bottle or a heat pad (like the ones you can get from a chemists for muscle pain) and place it around the pipe at the section where the water has frozen.

Remove any ice that comes out of the pipe. Once you think the pipe is clear, try restarting your boiler.

Reset your boiler

Once thawed, the boiler must be reset. Hold in the reset button for 10 seconds and then wait for 2 to 3 minutes for the boiler to refire.

Be extremely cautious when attempting to identify and thaw the condensate pipe. You should only attempt to thaw a condensate pipe that is at ground level and which you can easily reach. Under no circumstances should you attempt to thaw a condensate pipe which is higher than you can comfortably reach without the assistance of a professionally trained engineer.

What is a condensate pipe?

Most modern boilers have a condensate pipe that transports water away from the boiler. To improve efficiency, the boiler removes as much energy from the flue’s gases as possible. Some of this gas cools and turns into a small amount of water. The pipe transports this steady dribble of water away from the boiler and into a drain.

Why do these pipes freeze?

The pipes run outside your home to reach a drain. During the cold, winter months the acidic water is prone to freezing. If the water freezes in the pipe it creates a blockage. The boiler shuts down to prevent water flooding the entire boiler system.

Frozen water pipes

If you are experiencing difficulties with frozen pipes:

  • Turn off the stop tap (normally under your sink)
  • Put your central heating on, applying a gentle heat.
  • If you have frozen waste pipes (from your kitchen sink/bathroom), try pouring a kettle of warm water on the affected area

Good practice during a bad cold spell

  • Keep yourself warm!
  • Try to keep your heating turned on. This will mean a greater cost of fuel, but it can stop pipes freezing
  • Keep a supply of drinking water in bottles, and perhaps a bucket or two of water for toilet flushing
  • Keep any temporary heating devices handy, you may need them if your boiler breaks down
  • Keep an eye on neighbours to check that they are ok

We advise you have adequate home content insurance to cover you in case of emergencies.