Frozen condensate pipe? How to thaw it
A frozen condensate pipe is the most common reason condensing boilers stop in freezing weather. You can often thaw it yourself in minutes.
Every cold snap, our phones fill up with the same call: the boiler has stopped, it is gurgling, and the display shows a fault. Very often it is a frozen condensate pipe, and you can fix it yourself.
What the condensate pipe does
Modern condensing boilers produce water as they run. A plastic pipe, usually white or grey and about 20 to 30mm wide, carries it to a drain. When part of that pipe runs outside, it can freeze in sub-zero weather, the water backs up, and the boiler shuts down to protect itself.
Signs it has frozen
- The weather is below freezing
- A gurgling noise from the boiler or pipe
- The boiler shows a fault or lockout code and will not restart
How to thaw it
- Find where the plastic pipe leaves the boiler and follow it outside.
- Find the frozen section, usually at the lowest point, a bend or the open end.
- Pour warm water (not boiling) over it from a kettle or watering can, or hold a hot water bottle against it. Boiling water can crack the pipe.
- When it is clear, reset the boiler.
Take care on icy ground, and do not climb to reach a pipe high on a wall.
Stop it happening again
We can reroute the pipe internally, increase its size, or lag the outside section. Ask about it on your next service.
If the boiler still will not start, call Lee on 020 8050 5913. If he can talk you through it, there is no charge. Otherwise, book a boiler repair.
Stuck? Call Lee.
If you are not sure it is safe, stop and call. Advice by phone is free.
020 8050 5913
