BoilerFaultCodesWarmhaus rE99 Fault Code
Also written as RE99 — same fault.
The Warmhaus rE99 fault code means: your boiler has encountered a general electronic system error and needs to be restarted to clear its memory.. It appears on 1 Warmhaus model in our database.
Technical description: An error has been detected in the Combi, try resetting the boiler.
What causes the Warmhaus rE99 fault?
This fault occurs when the boiler's internal computer experiences a communication glitch or a software conflict between the control board and the display. It is essentially a 'electronic crash' that prevents the system from processing safety checks, causing the boiler to shut down for protection. In many cases, it is a temporary error caused by a power surge, but persistent codes often indicate the main circuit board is failing to retain its programming.
DIY fix possible
Locate the 'Reset' button on the boiler control panel.Press and hold the button for 2-3 seconds until the display changes.Wait for the boiler to complete its startup sequence to see if the heating resumes.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Warmhaus models that show the rE99 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Warmhaus rE99 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