BoilerFaultCodes.com
S.31 Low Information

Your boiler is currently set to provide hot water only, and the central heating has been disabled because it is in summer mode.

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: summer mode

What causes this fault?

This status occurs because the central heating function has been manually switched off, leaving only the hot water operational. It is usually caused by the user or an engineer adjusting the control dial or digital settings to a 'hot water only' position. There is no actual mechanical fault with the boiler; it is simply following the instruction to ignore calls for heating.

This is most common during the spring and summer months when homeowners intentionally deactivate their heating to save energy.

Typical repair cost £0 (including labour)

DIY fix possible

Locate the temperature control knob or buttons for the central heating on the control panel.Increase the heating temperature setting or turn the dial clockwise to exit summer mode.Ensure your room thermostat or programmer is also calling for heat.

Find a Gas Safe engineer

Search the official register for a qualified engineer in your area.

Gas Safe Register →

Protect yourself from future repair bills

A boiler cover plan would cover faults like S.31 — no call-out fees, no surprises.

Top rated
OpenFix
Boiler & heating care plans
Get a quote →
Hometree
from £12.95/month
Get a quote →
HomeServe
from £8.00/month
Get a quote →

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

Glow-worm Ultracom 24cx 30cx is discontinued — time for a new one?

Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.

UK's #1 online installer
Boxt
Fixed-price online quotes. Next-day installation.
Get a free quote →
Heatable
Instant online boiler quotes from £1,499.
Get a free quote →
iHeat
Fast installation. Price match guarantee.
Get a free quote →

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

Related fault codes