Troubleshooting
55
Diagnostics
(continued)
Retrieving an acknowledged fault message
1.
Press “
“ for approx. 3 sec.
2.
Press “
⊕
/
“ to select the
acknowledged fault.
Retrieving fault codes from the fault memory (fault history)
The ten most recent faults are saved and can be scanned.
The faults are in order of date, so the most recent fault is fault number 1.
1.
Press “
rw
“ + “
”
simultaneously for approx. 2 sec.
2.
Press “
⊕
/
“ for individual fault
codes.
3.
Note! All saved fault codes can be
deleted by pressing “
“.
4.
Press “
”
to finish scan.
Fault codes
Fault code on display
System behavior
*1
Cause
Corrective action
0F
Control mode
Service
Service the equipment.
After the service, reset
coding address “24” to”0”.
10
Boiler operates based on
outdoor temperature of 32°F
/ 0°C
Outdoor temperature sensor
shorted out
Check the outdoor
temperature sensor
(see page 60).
18
Boiler operates based on
outdoor temperature of 32°F
/ 0°C
Outdoor temperature sensor
cable broken
Check the outdoor
temperature sensor
(see page 60).
20
Regulates without supply
temperature sensor
(low-loss header)
System supply temperature
sensor shorted out
Check the low-loss header
sensor (see page 60).
28
Regulates without supply
temperature sensor
(low-loss header)
System supply temperature
sensor cable broken
Check the low-loss header
sensor (see page 60).
30
Burner blocked
Boiler water temperature
sensor shorted out
Check the boiler water
temperature sensor
(see page 60).
38
Burner blocked
Boiler water temperature
sensor cable broken
Check the boiler water
temperature sensor
(see page 60).
5
4
4
3
2
0
7
v
1
.5
I
18
Fault history
1
