If you do have a combination/condensate boiler there is a quick
and easy solution to get the heating back up and running without
having to wait for a gas engineer to visit – just follow the advice
If you don’t feel confident defrosting the pipe yourself, don’t
worry, ring our Technical Support Service on 0808 126
3123 or 01302 735191.
How do I know if I have a combination/condensing boiler
with a condensate pipe that could freeze?
If your boiler is a Baxi/Potterton Duotec, Baxi/Potterton Solo,
Vokera Mynute, Glowworm Hxi/Cxi, or a Vokera Unica, then it’s
likely that you have a boiler that will have a condensate pipe
What does the condensate pipe do?
The boiler naturally produces a small amount of waste gas which
turns to water as it cools. The condensate pipe drains this water
How do I know if my boiler has a condensate
Look under the boiler to see if there is a plastic pipe - It’s
usually white and around 20mm (about ¾”) wide. The pipe should run
to the outside of your home and should always run into a drain.
An example of a condensate pipe is shown below. The
condensate pipe is the diagonal pipe running along the side of
Why does it freeze?
The water dripping through the pipe can freeze
in cold weather, preventing it from draining away. When this
happens the boiler will shut down. To fix the problem the frozen
water needs to be cleared.
How do I know if my boiler has stopped working because
the condensate pipe is frozen?
Check your boiler for an error code:
- if you have a Baxi/Potterton boiler displaying ‘E1’ ‘33’ fault
- Vokera Unica or Vokera Mynute displaying the fault code
then check the condensate pipe. If it is NOT
frozen, ring the Technical Support Service on 0808 126
3123 or 01302 735191.
If it IS frozen and you feel able try to
defrost it yourself then defrost the condensate pipe and reset your
boiler following the instructions below.
How do I defrost the condensate pipe?
There are two ways to do this:
1) Pour hot water on the outside of the pipe. Don’t
use boiling water to do this and only pour over the outside of the
condensate pipe. Do not attempt to pour water down the
pipe. Be careful to avoid any slips and trips by
ensuring you do not get water on the path, as this will
2) Use either a hot water bottle or a heat wrap and place it
around the pipe at the section where the water has frozen.
How do I reset the boiler?
Once defrosted, you can reset your boiler by turning the
Selector switch to the Reset position and holding for at least 5
seconds. Remember, some boilers go through an electronic checking
cycle after being re-set: this can take up to 15 minutes.
I’ve defrosted the condensate pipe, reset the boiler and
it works fine - until it reaches a certain temperature, then it
cuts out. What’s wrong?
The frozen pipe may have caused the boiler to flood causing an
ignition fault. Try switching the boiler off for a few hours. If
this doesn’t rectify the problem ring the Technical Support Service
on 0808 126 3123 or 01302
Some things to remember …
- Never try to thaw a condensate pipe that cannot be easily
reached or disconnect the condensate pipe in the process.
- Use extreme caution at all times when trying to find or thaw
the condensate pipe.
What other issues can stop your combination boiler
working in severe weather conditions?
Combination boilers work by heating hot water on demand: they
take water straight from the mains supply, not from a tank. In
severe weather conditions the mains water supply to your home can
Try running your taps: if there is no water from any of your
taps the mains have probably frozen. If this happens you won’t be
able to use your combination boiler until the mains defrost.
Regardless of whether you have a combination boiler; a
condensate boiler; a gas fire back boiler; a wall mounted boiler;
or a solid fuel appliance, switch your boiler off or let your fire
go out until the water comes back on. Keep checking your taps. When
the water comes back on you can use your appliance
Unfortunately there is nothing we can do to repair your boiler
if your water supply has frozen.