Winter fault
Frozen condensate pipe — fix and prevention across Somerset
Every winter cold snap generates a wave of frozen condensate calls. The immediate fix is a warm compress; the real fix is either rerouting the pipe indoors or upsizing and insulating the external run.
For: Homeowners hit by a cold-snap boiler lock-out
Why it keeps happening
Original installs often ran 22mm plastic condensate downpipes outside for cost. Below –3°C, water freezes inside them. Modern practice is to run internal, then in 32mm insulated externally where unavoidable — with a shielded terminal.
The permanent-fix package
- Immediate thaw and boiler restart
- Assessment of run — internal reroute or upsize
- 22mm to 32mm upsize where staying external
- Class-O insulation over the whole external length
- Trace heating cable where routing is genuinely stuck outside
Frequently asked
- Can I thaw it myself?
- Warm (not boiling) water in a jug down the pipe, or a hot-water bottle wrapped around it. Never a heat gun or naked flame.
- Will insulation alone fix it?
- Below –5°C, no — insulation slows the freeze but doesn't stop it. Upsize plus insulation is the reliable answer.
- Is the boiler damaged?
- No — it locks out precisely to avoid damage. Once the pipe is clear it starts normally.
Fix it properly
One visit to thaw, reroute or upsize, and insulate. Same problem doesn't return next winter.
Related solutions
Core services
Further reading
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