Medium
E.02 .47 on Baxi Assure System

Your boiler is having trouble communicating with an external control, such as your thermostat or programmer, preventing it from knowing when to turn the heating on.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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

Connection to external device unsuccessful ELECTRICAL CONNECTION ERROR Start the auto-detect function (parameter AD) Check the electrical connections of external devices.

From this model's manual
Verified against the Baxi Bm Baxi B Basic System 2 600 800 Assure 500 Isim installation & service manual, page 50.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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 →
Boiler cover options

Avoid the next call-out bill

A cover plan would handle faults like E.02 .47: no call-out fees, no surprise bills.

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 guides you might find useful

Boiler won't turn on — 9-step checklist

Work through these before the call-out.

Read →

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 →