E1 253
Worcester Bosch Flame Stability / Combustion Disturbance

Boiler intermittently locks out with E1 253, often during windy conditions.

Advertisements

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Advertisements

Possible Causes

Flue terminal affected by wind, Incorrect flue installation, Blocked or partially blocked flue, Incorrect gas/air ratio

How to Fix / Troubleshooting

Safety first: Do not modify the flue yourself. Gas and flue work must be carried out by a qualified engineer.

  • Observe conditions: Note whether the fault occurs mainly during high winds or storms, which can indicate flue terminal issues.
  • Visual flue check: From outside, ensure the flue terminal is correctly positioned and not obstructed.
  • Engineer tasks: A professional should inspect the full flue route, check for correct terminal clearances, verify combustion with a flue gas analyser, and adjust or replace components as necessary.
Advertisements

Repair Difficulty

Professional Required 5/5

Required Part

Flue System
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements