System Faults - Viessmann S3HA Series Installation, Operating And Service Instructions

Service

System Faults

System faults are displayed on the touch screen user
interface.
System Fault System Characteristics
Display
Temp Sensor Vitotrans is not producing DHW.
T1A/B Fault System pump will not run.
No boiler demand signal available.
Pump P1 Vitotrans is not producing DHW.
Dead Head System pump will remain powered
Fault but will not run.
No boiler demand signal available.
Safety High Vitotrans is not producing DHW.
Limit System pump will no longer be
powered.
No boiler demand signal available.
Flow Sensor Vitotrans will not respond to
Fault demand for DHW.
Temp Sensor Vitotrans will continue normal
T2 Fault operation, DCW temperature
displayed as "0ºF".
Temp Sensor Vitotrans will continue normal
T4 Fault operation, system return
temperature displayed as "0ºF".
Temp Sensor Vitotrans will continue normal
T5 Fault operation, DHW storage tank
temperature displayed as "0ºF".
60
Vitotrans 300 Installation, Operating and Service
Note: Carry out measures in the described order.
All system faults are saved to the fault memory.
Cause
Lead break or faulty sensor
T1A/B.
System pump P1 has experienced
excessive head pressure and is
not able to provide flow.
The DHW supply temperature has
exceeded the setting of the fixed
high limit.
No flow of domestic water.
Faulty sensor.
Lead break or faulty sensor T2.
Lead break or faulty sensor T4.
Lead break or faulty sensor T5.
Measures
Check sensor wiring connections
and sensor.
Replace sensor if necessary.
Check internal isolation valves
to ensure they are open.
Wait for the DHW to cool.
Reset the fixed high limit.
Verify domestic water flow
through unit.
Check sensor power supply.
Check for signal.
Refer to page 63.
Replace sensor if required.
Check leads and sensor, replace
if required.
Check leads and sensor, replace
if required.
Check leads and sensor, replace
if required.