BoilerFaultCodesGrant Blinking RED Fault Code
Also written as BLINKINGRED — same fault.
The Grant Blinking RED fault code means: your boiler has detected that it is running too hot and has automatically slowed itself down to prevent any damage to its internal components.. It appears on 6 Grant models in our database.
Technical description: Thermal self-protection mode. The fluid temperature exceeds the maximum value at a specific ambient temperature. The pump will automatically reduce power consumption, speed, and performance.
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 Blinking RED: 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 Blinking RED fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Grant Blinking RED fault code information on this page is sourced and cross-checked against the official Grant service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 7 July 2026