Low
1-b7 on Worcester Bosch Greenstar 8000 Life Combi

Your boiler is receiving an incorrect or unusual temperature request for your hot water from the external heating controls.

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

DHW set temperature: Setting value of the hot water temperature demanded by the heating controller.

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 your external thermostat or heating app sends a temperature command that the boiler doesn't recognize or can't process. The most common reason is a communication glitch or a software mismatch between your wireless controller and the boiler's internal computer.

DIY fix possible

Check your thermostat or heating app to ensure the hot water temperature is set to a normal level (typically 50-60°C).Turn the boiler off and back on at the main isolation switch to reset the communication between the controller and the boiler.Ensure any smart home batteries in your thermostat are not low, as this can cause communication errors.

Find a Gas Safe engineer
Search the official register →

Avoid the next call-out bill

Monthly cover means no unexpected bills when your boiler breaks down.

Approved partner
Domestic Appliance Guard
Unlimited call-outs, 24/7 helpline, no price-hike promise
Get a quote →

Affiliate links. We may earn a commission at no extra cost to you.

Related fault codes

All 151 fault codes on the Greenstar 8000 Life Combi

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

Related guides you might find useful