BoilerFaultCodesWhat the manual says
Manufacturer manualMounting fault S3
From this model's manual
Verified against the Intergas/Intergas Xclusive installation & service manual, page 64.
What causes this fault?
This fault occurs when the boiler's control board loses signal or receives an incorrect reading from a specific internal temperature sensor. The most common reason is that the sensor itself has failed due to wear, or the wiring connecting it to the main computer has become loose or damaged.
Engineer required
This is a high severity fault. Stop using the boiler and call 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 f016: no call-out fees, no surprise bills.
Approved partner
Get a quote →
Domestic Appliance Guard
Unlimited call-outs, 24/7 helpline, no price-hike promise
Affiliate links. We may earn a commission at no extra cost to you.
Related fault codes
All 23 fault codes on the Xclusive 24
Seeing a different code? Every code this model can display, in one place.