Viessmann VITODENS 300 Service Instructions Manual page 92

Troubleshooting
Repairs
(cont.)
10. Install in reverse order using new
gaskets. Lubricate the new gas-
kets/seals.
Checking the temperature limiter
Checking and replacing pressure differential sensor
Check the sensor in case of fault messages concerning the differential pressure
sensor:
&
Correct installation
92
11. Danger
Escaping gas leads to a
risk of explosion.
Check the gas connections
for soundness.
Check all fittings and the flange
for soundness.
If the burner control unit cannot be
reset after a fault shutdown, although
the boiler water temperature is below
approx. 75 °C:
&
Pull the leads from temperature lim-
iter A.
&
Check the continuity of the tempera-
ture limiter with a multimeter.
&
Remove faulty temperature limiter.
&
Install a new temperature limiter.
&
After commissioning, press reset
button E on the control unit.