Viessmann Vitotwin 300-W - Page 133

133
Fault mes-
sage
Cause Remedy Re-
set-
ting
"301: Eng
head overt
SW"
Stirling head control temper-
ature too high.
Check spring length; adjust if
necessary (see page 77).
Check electrical output (code
8200 in diagnostics engine).
If the output < 500 W, notify
Viessmann Technical Serv-
ice.
Check the temperature dif-
ferential at the Stirling head
thermocouples in steady-
state condition (code 7764
and 7764 in input/output
test). If the differential
> ± 50 K, reposition the ther-
mocouples (remove yellow
connection plug and plug in C
to L or L to C). Then check
electrical output (code 8200
in diagnostics engine). If the
electrical output is too low,
replace the thermocouples.
If the fault recurs, notify
Viessmann Technical Serv-
ice.
AR
"302: Eng
head t'cou-
ple diff"
Temperature differential be-
tween the Stirling head con-
trol and limit thermocouple is
too high.
Check plug-in connection
X205, connecting cables and
plugs to thermocouples on
the Stirling engine.
UR
"303: Eng
head t'cou-
ple cont"
Stirling head control thermo-
couple faulty.
UR
"304: Eng
head t'coupl
lim"
Stirling head thermocouple
limiting fault.
UR
Troubleshooting
Fault messages
(cont.)
5618 294 GB
Service