Check the official guidance for your boiler. Only consider the manufacturer’s permitted homeowner steps where the correct pipe is safely accessible. Do not use boiling water, remove boiler covers or work at height.
Gas smell or suspected carbon monoxide?
Get outside into fresh air and call 0800 111 999 from a safe place. Do not wait for an online booking. Read emergency guidance
Do not diagnose it from the weather alone.
Note the fault message and whether the problem started during freezing conditions. Other boiler faults can occur at the same time. If you cannot identify the pipe confidently, ask for assistance instead of treating an unknown pipe.
Use the manufacturer’s own guidance.
Worcester Bosch publishes guidance for safely accessible frozen condensate pipes, including the distinction between warm and boiling water. Follow the instructions relevant to your appliance and do not apply a generic method to an inaccessible or uncertain installation.
Keep access and electrical safety first.
Do not climb on furniture or ladders to reach pipework, open the boiler case or use electrical heaters in an unsafe wet area. A person who cannot safely carry out a permitted user step should not feel obliged to attempt it before asking for help.
A returning problem deserves a review.
If the problem recurs, the pipe route or protection may need professional assessment against the appliance instructions. Clearing a temporary blockage is not the same as correcting an unsuitable installation.
Use the normal repair route for unresolved faults.
Explain the model, message and the conditions in which the fault appears. Do not select a routine service simply because the boiler is also due one. Gas or carbon-monoxide concerns still use the emergency route, whatever the weather.
Useful official guidance
General information does not replace the instructions for your appliance or an inspection of your home.
Worcester Bosch: frozen condensate guidanceHSE: gas safety at homeCadent: what to do if you smell gas