BoilerFaultCodes.com
4.13 High Lockout

Your boiler has lost power or the screen has failed, meaning it will not operate and you cannot see any settings or status messages.

Call an engineer soon

Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description: No Display

What causes this fault?

This fault occurs when the electrical connection between the boiler's internal computer and the front screen is broken or lost. The most common reason is a failure of the display circuit board itself, or a blown fuse on the main control board caused by an internal electrical surge.

Typical repair cost £100-350 (including labour)

DIY fix possible

Check if other appliances in the house are working to rule out a general power cutCheck your home's main fuse box (consumer unit) to see if a circuit has trippedEnsure the boiler's power switch (usually a fused spur near the unit) is turned on

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 4.13 — 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.

Could it be time for a new boiler?

If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.

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