E28 High

Johnson Starley E28 Fault Code

The Johnson Starley E28 fault code means: your boiler's temperature sensor responsible for monitoring the warm air flow has detected an electrical fault and is preventing the system from running safely.. It appears on 1 Johnson Starley model in our database.

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: Duct thermistor short circuit
Typical repair cost £120-£190 (including labour)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Johnson Starley models that show the E28 fault code

Click a model for the full fault code list and model-specific repair notes.

Source

Johnson Starley E28 fault code information on this page is sourced and cross-checked against the official Johnson Starley service / installation manuals for each affected model.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026