Low
i1 on Worcester Bosch Greenstar Heatslave II

This code is not an actual fault; it is simply showing your boiler's current operating status or mode of activity while it is running normally.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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.

Technical description

Current status related boiler status code - Every operation and mode of the boiler has a related boiler status code. The boiler status code is displayed on the screen as a 3 figure number.

Engineer required

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

Find a Gas Safe engineer
Search the official register →

Related guides you might find useful

Yellow or orange flame — CO safety

Safety-critical — turn off, read this.

Read →

Is boiler cover worth it?

Break-even maths on monthly cover.

Read →

When to replace your boiler

7 signs repair isn't worth it anymore.

Read →