34
Maintenance and care
: Trouble shooting
A B C
Error
code Fault
Possible cause
Action
required
Reset
4 R
1
E 4
Extract air tem-
perature sensor
(T1)
Control board
measure that
temperature
sensor is either
open or shortcut
circuit
Temperature
sensors are not
mounted cor-
rect
Mount temperature
sensors correct
Automatic reset
if temperature
is within normal
range for 30
seconds
Resistance
in one of the
temperature
sensors is too
low or too high
Change tempera-
ture sensors
Resistance in
temperature
sensors are OK
Change control
board
5 R
1
E 5
Supply air tem-
perature sensor
(T2)
Control board
measure that
temperature
sensor is either
open or shortcut
circuit
Temperature
sensors are not
mounted cor-
rect
Mount temperature
sensors correct
Automatic reset
if temperature
is within normal
range for 30
seconds
Resistance
in one of the
temperature
sensors is too
low or too high
Change tempera-
ture sensors
Resistance in
temperature
sensors are OK
Change control
board
6 R
1
E 6
Extract air tem-
perature sensor
(T3)
Control board
measure that
temperature
sensor is either
open or shortcut
circuit
Temperature
sensors are not
mounted cor-
rect
Mount temperature
sensors correct
Automatic reset
if temperature
is within normal
range for 30
seconds
Resistance
in one of the
temperature
sensors is too
low or too high
Change tempera-
ture sensors
Resistance in
temperature
sensors are OK
Change control
board
7 R
1
E 7
Exhaust air tem-
perature sensor
(T4)
Control board
measure that
temperature
sensor is either
open or shortcut
circuit
Temperature
sensors are not
mounted cor-
rect
Mount temperature
sensors correct
Automatic reset
if temperature
is within normal
range for 30
seconds
Resistance
in one of the
temperature
sensors is too
low or too high.
Change tempera-
ture sensors
Resistance in
temperature
sensors are OK
Change control
board
8 -
0
E 8
Room air tem-
perature sensor
(T5)
Only shown on wireless remote
Automatic reset
9 -
-
E 9
Not used