BoilerFaultCodes.com
S.4 Low Information

Your boiler is operating normally and is currently in the process of starting up the burner to provide heat or hot water.

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: Burner ignited

What causes this fault?

This is not a fault, but rather a status message indicating that the boiler has successfully lit the flame. It confirms that the internal ignition sequence is complete and the unit is now producing heat for your radiators or hot water. You will see this code every time the boiler starts up as part of its normal, healthy operation.

Typical repair cost £0 (including labour)

DIY fix possible

This fault may be fixable without an engineer. Check your manual first.

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.4 — 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.

Related fault codes