Medium
1-d3 on Worcester Bosch Greenstar 8000 Life Combi

Your boiler is reporting an issue with the pump that circulates fluid between your solar panels and the water tank.

Book a service

This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

What the manual says

Manufacturer manual

Collector pump: Is only displayed, if a solar module is connected.

Shared across the Greenstar 8000 Life range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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 system detects that the pump responsible for moving heated fluid from your solar panels to your hot water tank is not functioning correctly. The most common reasons are a mechanical failure within the solar pump itself, a faulty sensor failing to read the fluid temperature, or a communication error between the solar control module and the boiler.

This fault is more common during the summer months when high levels of solar radiation put the pump and sensors under maximum operating demand.

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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All 151 fault codes on the Greenstar 8000 Life Combi

Seeing a different code? Every code this model can display, in one place.

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