BoilerFaultCodesWarmhaus E77 Fault Code
The Warmhaus E77 fault code means: your boiler has detected an issue with its internal combustion levels and cannot regulate the gas flame safely.. It appears on 1 Warmhaus model in our database.
Technical description: Current values reached – check combustion values and CO2 calibration, try resetting the boiler if this fails. Either the board or the valve will need replacing.
What causes the Warmhaus E77 fault?
This fault occurs when the boiler's internal sensors detect that the gas and air mixture is no longer burning within safe, controlled limits. It usually happens because the gas valve is failing to regulate the flow correctly or the main control board has lost the ability to calibrate the flame, leading the system to shut down for safety.
DIY fix possible
Press the reset button once to see if the error clearsCheck that your gas supply is active and other gas appliances are workingIf the fault persists after one reset, turn off the boiler and call a Gas Safe engineer
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Warmhaus models that show the E77 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Warmhaus E77 fault code information on this page is sourced and cross-checked against the official Warmhaus service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026