Medium
31 on Alpha E-Tec Plus 10 / 18

Your boiler has lost its connection with the remote thermostat or controller, meaning they are no longer talking to each other.

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

Loss of connection between the boiler and Alpha Climatic control unit

From this model's manual
Verified against the Alpha E Tec Plus 10 18 installation & service manual, page 48.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check if the batteries in your Alpha Climatic control unit need replacing.Ensure the controller is within range and has not been moved too far from the boiler.Reset the boiler by turning the selector switch to the 'RESET' position for 5 seconds.

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 31: 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 fault codes

E31View →

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 →