BoilerFaultCodesGrant Overheat Fault Code
Also written as OVERHEAT — same fault.
The Grant Overheat fault code means: your boiler has automatically turned itself off because it has become too hot, which is a safety feature to prevent damage or dangerous conditions.. It appears on 8 Grant models in our database.
Technical description: The 'OVERHEAT' red indicator on the control panel will flash indicating that the overheat thermostat has operated. This will automatically switch off the boiler in the case of a control malfunction causing overheating.
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 →Avoid the next call-out bill
A cover plan would handle faults like Overheat: no call-out fees, no surprise bills.
Affiliate links. We may earn a commission at no extra cost to you.
Grant models that show the Overheat fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Grant Overheat fault code information on this page is sourced and cross-checked against the official Grant service / installation manuals for each affected model.
- Grant Euroflame Condensing manual (PDF)
- Grant Vortex 15-20 manual (PDF)
- Grant Vortex 20-26 manual (PDF)
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026