Fault Finding - Buffalo NBB3 Installation And Operating Instructions Manual

FAULT FINDING

The control panel displays information that can help with fault diagnosis. Before
calling for service, draw off a litre of water, clear the fault code by pressing the Fn
button and turn the boiler off and on again at the supply. If the fault persists, call
service for advice.
Message displayed
FILTER
CAUTION
SEE MANUAL
STANDBY
FILTER
FAULT
SEE MANUAL
STANDBY
FILTER
FAULT
SEE MANUAL
STANDBY
FILTER
FAULT
SEE MANUAL
STANDBY
IS 619 ECN 3949
Scale on level sensors
DESCALE Boiler overfilling
CLEAR
Water turned off
NO WATER
Inlet hose kinked or
blocked
Water pressure too high or
low
Drain valve open
CLEAR
Boil dry/overheat protector
NOT HEATING
tripped
Temperature sensor fault
Element failed
PCB fault
Faulty or loose connection
CLEAR
Temperature sensor fault
THERMISTOR
CLEAR
Page 9 of 10
Possible causes Corrective action
Descale
Check water inlet valve
Check water supply and
drain valve
Call service if fault
persists
Check connections
Call service if fault
persists
Call service