1.
&
Boiler water temperature sensor:
Pull the leads from boiler water
temperature sensor
A
and
check the resistance.
&
Cylinder temperature sensor: Pull
plug
%
from the cable harness at
the control unit and check the
resistance.
&
Flow temperature sensor: Pull
plug "X3" from the control unit
and check the resistance across
terminals "X3.4" and "X3.5".
2.
Check the sensor resistance and
compare the actual values with the
curve.
3.
Replace the sensor in case of
severe deviation.
Danger
The boiler water tempera-
ture sensor is immersed in
the heating water (risk of
scalding).
Drain the boiler before repla-
cing the sensor.
Checking the flue gas temperature sensor
The flue gas temperature sensor locks out the boiler when the permissible flue
gas temperature is exceeded. Reset the interlock after the flue gas system has
cooled down by pressing "
E
RESET".
Repairs
(cont.)
84
Troubleshooting
5692
673
GB
Summary of Contents for VITODENS 300-W
Page 111: ...Parts lists cont 111 Parts lists 5692 673 GB...
Page 112: ...Parts lists cont 112 Parts lists 5692 673 GB...
Page 113: ...Parts lists cont 113 Parts lists 5692 673 GB...
Page 114: ...Parts lists cont 114 Parts lists 5692 673 GB...
Page 121: ...121 5692 673 GB...
Page 122: ...122 5692 673 GB...
Page 123: ...123 5692 673 GB...
