Quick checks before you call
Check the boiler display for an error code and note it down. Check the pressure gauge — many systems run at around 1–1.5 bar when cold. Make sure the gas and electricity are on, your thermostat is calling for heat, and the timer is set correctly.
In freezing weather, a frozen condensate pipe is a common cause of lockouts. Never attempt to open the boiler casing or work on gas components yourself.
Repair or replace?
If your boiler is relatively new, a repair is usually the right call. If it's older, needs an expensive part, or keeps breaking down, we'll tell you honestly whether replacement may offer better value — and leave the decision with you.
Carbon monoxide
Signs of a problem include a lazy yellow or orange flame, soot or staining around the appliance, and symptoms such as headaches, dizziness or nausea that ease when you leave the house. If you suspect carbon monoxide, turn the appliance off, get fresh air, leave the property, call 0800 111 999 and seek medical advice. Every home with a gas appliance should have an audible CO alarm.