Viessmann MatriX radiant burner Service Instructions Manual page 29

Diagnostics
(cont.)
Fault System
code characteristics
32 Burner control unit in
fault state
35
36 Fan speed during
start−up or operation
stays outside its set
range longer than
5 s, speed for ignition
setting or start
output during
operation is not
achieved
37 Fan does not reach
set speed
42 Burner control unit
remains in start−up
position; no start−up
in spite of heat
demand
4E Burner control unit in
fault state
Scrolling Constant start
change− attempt
over
display:
1 2 3
4 5 7
Cause
Error in feedback
from auxiliary
start−up valve, output
relay does not
activate
Error in feedback
from ignition, output
relay does not
activate
Fan faulty, cables
faulty or broken
Fan faulty, cables
faulty or short
circuited, fan blocked
by debris
Safety chain broken
Internal error
Cores L 1 and N at
control unit mains
supply interchanged
Troubleshooting
Remedy
Replace burner
control unit
Check cables,
replace fan
Check cables,
replace fan, remove
debris
Check jumper (B 2) of
safety chain
Replace burner
control unit
Check mains supply
and swap cores
29