• Lisa Kaufenstein

How to deal with frozen condensate pipes


Condensate Pipes

Condensate boilers extract as much heat as possible from the waste flue gas, which is what makes them highly efficient. When this type of boiler is in operation it can produce as much as two litres of condensate per hour. Your boiler is working perfectly and efficiently when condensed water is running through its condensate pipe. The condensate has to be routed away from the appliance and towards the wastewater or drainage system.


Why can condense pipes freeze?

The condensate pipe leads from the boiler to a household drainage system or soak way. It is advised that this is through an internal route as much as possible, so the warm condensate is not met with cold outside temperatures in winter. However, it is legal to run this pipe along the outside of the house if internally is impossible. Long periods of cold weather can then cause this pipe to freeze and can affect the boiler operation.

If the condensate pipe is running externally there are some things to consider:

The pipework should:

  • Be fully insulated

  • Fall continuously away from the boiler at an angle of at least 3 degrees

  • Have a diameter of a minimum of 32mm

  • Be shorter than 3m

  • Have no or as few as possible bends

  • End under a drain cover and within an air break in order to prevent wind chill


Safely thawing a frozen condensate pipe

If you have an external condensate pipe, cold weather can cause it to freeze which might lead to your boiler not working. Your boiler might make a gurgling noise and if it has a digital display, it might show an ‘EA’ error code.

A frozen condensate pipe is nothing to worry about. Generally, you can thaw it safely without having to call a plumber.


3 Steps to defrost your condensate pipe

1. Look for your outdoor pipe, it is usually made out of white plastic and looks similar to a waste pipe. Check that it is connected to your boiler.

2. If it is at ground level and safely accessible, pour warm water (not boiling) over the length of the pipe. Alternatively, put a hot water bottle or heat pad on the section of the pipe you suspect to be frozen.

3. 3. Reset your boiler, if the pipe has defrosted it should start as normal.

Please remember to be extra careful when carrying hot water when it is icy outside. If it is still cold outside, any water you might spill on the ground will most likely freeze so beware of new icy patches.


6 views0 comments

Recent Posts

See All