What does the Ideal Mini F91 fault code mean?
The F91 fault code on the Ideal Mini boiler indicates a problem with the domestic hot water (DHW) system outlet. This typically suggests that there is an issue with the flow of hot water, which could be due to a blockage or a malfunctioning component.
Common Causes
- Blocked DHW Outlet: A blockage in the hot water outlet can prevent proper flow, triggering the F91 fault code.
- Faulty DHW Sensor: A malfunctioning sensor may incorrectly detect temperatures, leading to the fault code being displayed.
Can I fix it myself? (DIY)
It is recommended to call a Gas Safe Engineer for this issue, as it may involve gas or electrical components that require professional handling. Attempting to fix it yourself could pose safety risks.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for resolving the F91 fault code could be around £150 to £250, depending on whether a sensor replacement or blockage removal is necessary. This estimate includes parts and labour for a qualified engineer.