BoilerFaultCodesWhat the manual says
Manufacturer manualNO CH OPERATION BUT DHW WORKS OK
Shared across the Atlantic Combi range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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 90: 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 59 fault codes on the Atlantic Combi
Seeing a different code? Every code this model can display, in one place.
4.34.44.54.64.74.84.94.104.114.12828384858689F[-]F1F2F2 or Fn or LnF3F4F5F6F7F8F8 or L8F8/L8F9F9 or L9F9/L9FAFan faultFlame lossFlow thermistor faultFnFUIgnition lockoutL 2L CL[-]L1L4L4 or F4L5L5 or F5L6L8L9LnLow mains voltageLow water pressureNo DisplayOutside sensor faultOverheat lockoutPCB FaultReturn thermistor faultWater Pressure
Related guides you might find useful
No hot water but heating works
Almost always a stuck diverter valve on a combi.
Read →Hot water works but heating does not
On a combi it is usually the diverter valve. On a system boiler, the motorised valve.
Read →Radiator not heating up
One cold radiator is usually a stuck valve pin or trapped air.
Read →