F42
FAULT CODE
Glow-worm
Coding Plug Fault
High Severity
Engineer Required
The boiler coding plug is missing or cannot be read.
Step-by-Step Fix Guide
-
Step 1 Engineer only
A Gas Safe engineer should check the coding plug is correctly fitted
Gas Safe Reminder
Work on gas appliances must be carried out by a Gas Safe registered engineer. The steps above cover safe checks a homeowner can perform - any internal component replacement requires a qualified professional. If in doubt, always call an engineer.