Worcester Bosch Greenstar Boiler Not Working? How to Reset It

Discover how to reset your Worcester Bosch Greenstar boiler quickly and easily.

If your Worcester Bosch Greenstar boiler has suddenly stopped working or you’ve noticed a flashing blue light, don’t worry—this is often something you can fix yourself. In many cases, a quick reset is all that’s needed to get your heating and hot water back up and running. In this guide, we’ll show you exactly how to reset your Worcester Bosch Greenstar boiler safely and easily.

Top Reasons Your Worcester Bosch Greenstar Boiler Needs a Reset

Knowing why your boiler needs resetting can help you prevent the same problem from happening again. Some of the most common reasons include low water pressure, frozen condensate pipes (especially in colder weather), blocked air vents, or a faulty thermostat. Sometimes, a power cut or disruption in your gas supply can also cause your boiler to go into fault mode.

While a quick reset can often get your Worcester Bosch Greenstar boiler back up and running, repeated faults may point to something more serious—like a faulty sensor, diverter valve, or heat exchanger. Keep an eye out for any flashing lights or fault codes on the display, as these can give you helpful hints about what’s going wrong. If you find yourself resetting the boiler often, it’s probably time to call in a professional. Regular servicing and preventative maintenance are great ways to catch small issues before they turn into expensive repairs.

If your boiler keeps showing faults, don’t wait—get in touch with a qualified engineer to make sure your heating system is working safely and efficiently.

Worcester Greenstar CDi Classic Boiler Reset

Tools you’ll need to bleed your radiators:

Press and hold the reset button [2] for three seconds.

Once the reset button [2] and fault indicator [3] stop flashing, the reset is complete.

If the reset works, your boiler will go back to normal operation.
If it doesn’t, the alert code will show again, and the blue operation/fault light will keep flashing.

Worcester Greenstar Si & CDi Compact Boiler Reset

Press the “Reset” button to initiate the reset.

“Reset” and a tick will briefly appear on the display.

If the reset is successful, the boiler will resume normal operation.
If not, the alert code will reappear, and the blue operation/fault light will keep flashing.

Worcester Greenstar i Boiler Reset

Press the reset button briefly once to reset the appliance.

“Reset” and a tick will appear briefly on the display.

If the reset is successful, the appliance will return to normal operation.
If it isn’t successful, the alert code will reappear, and the blue operation/fault light will keep flashing.

Worcester Greenstar i Junior Boiler Reset

If there’s a fault, the reset button will flash once every second, and the blue mains indicator light will also flash.

Press and hold the reset button for about five seconds to reset the boiler. The reset button light will turn off once the reset is complete.

The mains indicator light will stop flashing.

Worcester Greenstar Ri Boiler Reset

If there’s a fault, the blue mains indicator light will flash.

To reset the boiler, turn the Central Heating temperature knob anticlockwise to the “RESET” position and hold it there for about five seconds. Then, turn the knob back to your original temperature setting.

Once the boiler resets, the mains indicator light will stop flashing, and the boiler should operate normally—depending on your programmer and room thermostat settings. If the power supply to the boiler has been interrupted, a reset fault may occur; simply follow the steps above to reset the boiler again.

Is your boiler still not working?

Sometimes, unfortunately, a simple reset isn’t enough to get your boiler back up and running. If your boiler keeps going back into fault mode you will now need to call a Gas Safe registered engineer.

PDF Gas & Heating have Gas Safe registered engineers ready to help. We can quickly diagnose and repair your boiler to get your heating back on track. Get in touch