How to prevent a Boiler condensate pipe from freezing

To help prevent your condensate pipe freezing, you can lag the pipe with waterproof and weatherproof lagging.

If your boiler has been installed with the plastic condensate pipe on an outside wall, the liquid inside the condensate pipe could freeze if the temperature drops below zero. If this happens, the boiler will shut down to protect itself. Time to prevent this from happening:

1. Maintain temperature inside your home: The number one thing you should do is regulate and maintain a steady temperature inside your home. Try to keep it above 60°F/16°C at all times, especially at night, even if you’re not home at the time.
2. Insulate exposed water pipes: Insulating water pipes in particular the condensate pipe which runs out from your boiler is the best prevention, you can buy pipe insulation from DIY shops.

We recommend that all customers ask a Gas Safe registered engineer to carry out any remedial work.

If your boiler has shut down and is showing error code E133 or E28, then your condensate pipe may be frozen. Please follow these steps to get your boiler up and running again:

• Switch your boiler off at the control panel, and turn off the electricity at the wall.
• Find where the pipe is frozen, usually the most exposed part of the pipe.
• Warm the condensate pipe across its exposed length using either a hot water bottle, a microwaveable heat pack or warm water poured from a watering can. Do not use boiling water straight from the kettle as this could damage the pipe.
• Turn the power back on at the wall and restart your boiler. Repeat the process until the boiler works again. 

As a temporary measure, it may help to turn the boiler thermostat (not the room thermostat) to maximum and run the boiler in ‘continuous’ mode, turning the room thermostat to 15°C at night. Turn back to the normal settings once the cold spell is over.

In the longer term, in order to prevent the pipe freezing, you can ask your Gas Safe registered installer to move the pipe so that it runs internally. Or, you could ask them fit a wider pipe, lag it to reduce the risk of freezing, install a trace heater along the pipe which warms it slightly when temperatures drop to freezing, or a combination of all of these.

Need technical support? Call our Baxi Customer Support technical helpline on 0344 871 1545

Baxi Customer Support helpline: 0330 678 0917