What does the Worcester Bosch Greenstar Si F76 fault code mean?
The F76 fault code indicates that there is an issue with the system pressure in the Worcester Bosch Greenstar Si boiler. This typically means that the pressure is either too low or too high, which can affect the boiler’s operation and efficiency.
Common Causes
- Low Water Pressure: This can occur due to leaks in the system or insufficient water supply, leading to inadequate pressure for the boiler to function properly.
- High Water Pressure: This may result from a faulty pressure relief valve or an issue with the expansion vessel, causing the system to exceed safe pressure levels.
Can I fix it myself? (DIY)
If the pressure is low, you can attempt to repressurise the system by using the filling loop to add water until the pressure gauge reads between 1-1.5 bar. However, if you are unsure or if the pressure is too high, it is strongly advised to call a Gas Safe Engineer to avoid any safety risks.
Estimated Repair Cost (2026 UK Prices)
The estimated repair cost for addressing the F76 fault could range from £100 to £250, depending on whether it involves simply repressurising the system or replacing components like the pressure relief valve or expansion vessel.