Unknown
e10 on Main MainEco

Main MainEco fault code e10

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

What the manual says

Manufacturer manual

Difference between the flow and return temperatures too great

From this model's manual
Verified against the Main/Main Maineco Combi System installation & service manual.
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 e10: 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.

All 61 fault codes on the MainEco

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

5v[05v[15v[25v[75v[105v[115v[125v[135v[155v[165v[175v[185v[195v[205v[215v[225v[25Code ACode BCode CCommunication faulte[00e[01e[02e[03e[04e[05e[06e[07e[08e[09e11e12e14e16e17e34e35e36e37e38e39e40e41Error code 1Error code 2Error code 3Error code 4Error code 5Error code 6Fan faultFlame lossIgnition faultMiscellaneousOverheat temperature protectionParameter errorReinitialisationResetting...Sensor errorTemperature protection

Related guides you might find useful

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 →

New boiler cost 2026

Realistic UK prices for a swap.

Read →