Boiler Breakdown: What To Do Before You Call an Engineer

2 October 2026 · 4 min read

A boiler breakdown is stressful, especially in a Scottish winter. A few safe checks can sometimes get the heating back on, or help the engineer find the fault faster.

If you smell gas

Do not touch switches. Open windows, turn off the gas at the meter and call the National Gas Emergency Service on 0800 111 999 straight away.

Check the basics

Make sure the power is on, the thermostat is set above room temperature and the timer is on. Check your gas supply is working at other appliances.

Check the pressure

Most combi boilers need around 1 to 1.5 bar when cold. If it is lower, follow your manual to top up, or ask an engineer.

Frozen condensate pipe

In freezing weather the plastic pipe outside can freeze and lock out the boiler. Pour warm (not boiling) water over it, then reset the boiler.

When to call us

If the boiler still will not run, shows a fault code or loses pressure again, contact a Gas Safe engineer. Never remove the boiler casing yourself.