Low
1-C6 on Worcester Bosch Greenstar 8000 Life & Style

Your boiler has detected that the water pressure in the system is outside of the normal operating range, which often means it needs topping up or has been overfilled.

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

System pressure: Current system pressure

From this model's manual
Verified against the Worcester Bosch Greenstar 8000 Life Style installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

What causes this fault?

This fault occurs when the internal sensor detects that the system pressure has dropped below 0.6 bar or risen above a safe maximum. The most common reason is a slow loss of water through the radiators or a leak, but it can also happen if the filling link was left open after topping the boiler up. When the pressure leaves this safe zone, the boiler's safety software restricts operation to prevent internal damage.

This fault is more common in autumn when homeowners first turn their heating back on after summer, as air can get trapped or seals may have shrunk during the period of inactivity.

DIY fix possible

Locate the internal or external filling link (often a blue lever or braided hose under the boiler).Slowly open the valve(s) until the pressure gauge on the display shows between 1.0 and 1.5 bar.Ensure both valves are closed tightly once the correct pressure is reached.

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