Help & Advice

How to unfreeze a frozen
condensate pipe

The boiler condensate pipe is the pipe that allows for water that comes from your central heating system to be disposed of. Some boilers condensate pipe may be connected to their wastepipe, but this is not always the case.

Some homes have external condensate pipes that are a weak spot during the winter times in the UK. During cold weathers, the condensate pipe could freeze, causing your boiler to stop working, leaving you without heating or hot water, and as this is a problem that would occur during the colder seasons, it makes this problem a bigger one when the house gets cold! Luckily, resolving this is easy even for houseowners with some simple DIY, therefore you will not need an engineer to visit you to sort this out allowing you to save money on repairs.

You will know if your boiler is experiencing this issue if you hear it making a gurgling noise. This may be a bit uncomforting to come across when you are not familiar with the issue, but know that it is safe as your boiler would most likely shut itself off to protect it from damage and display you a code which you could google to confirm the issue is indeed the condensate pipe.

You are likely to find the end of the condensate pipe where it can lead to a draining point for the water to go through. A visual inspection of this pipe should give you an idea of where exactly it is frozen.

In order to unfreeze the condensate pipe, you will need to heat water with your kettle or microwave, put the hot water into a jug, and slowly pour it over the frozen part of the pipe in order to allow it to melt. You may need to do this a few times or even put a hot water bottle around the condensate pipe for some time so the ice melts properly. Once your confident the ice has melted over, you can reset your boiler. You will know if the results were successful if the fault code on your boiler disappears and your boiler is operational again.

Some ways you can help avoid facing this issue again is by moving the pipe internally, change the angle of the pipe to avoid water build up, increase the diameter of the condensation pipe (all of which would require a gas safe engineer), or insulate the pipes to reduce the likelihood of it freezing over. This also helps you save money in the long run as it makes your central heating more efficient.