8 ope ra tio nal faults 64, 1 sen sor fai lure 64, 2 col lec tive error alarm 64 – Samson 5476 User Manual
Page 64: Col lec ti ve er ror alarm 64, Ope ra tio nal faults 64 - 65, Sen sor fai lu re 64, Operational faults, Sensor failure, Collective error alarm

8
Operational faults
Malfunctions or faults are indicated by the
icon blinking on the display.
8.1
Sensor failure
The following list explains how the controller responds to the failure of the different sensors.
Safety functions such as frost protection and excess temperature protection no longer work
when a sensor fails.
4
Outdoor sensor AF
: When the outdoor sensor fails, the controller uses a flow temperature
set point of 50 °C or the
Max. flow temperature (when the Max. flow temperature is smaller
than 50 °C).
4
Flow sensor in heating circuit VF1/VF2
: When the flow sensor is defective, the controller
continues to work with the associated valve in the 30 % valve position. DHW heating which
uses such a sensor to measure the charging temperature is interrupted. In systems Anl 4, 5, 6
and 11, the failure of flow sensor VF2 cause the DHW control valve to close.
4
Flow sensor in DHW circuit VF3
: When the flow sensor VF3 is defective, the DHW heating
takes place without change in lag/lead sequence.
4
Return flow sensor RüF1/RüF2
: The controller continues to function without the return tem-
perature limitation when the return flow sensor fails.
4
Room sensor RF
: The controller functions using the settings for operation without room sen-
sor when the room sensor fails. For example, optimization mode switches to the reduced op-
eration mode. Adaptation mode is interrupted. The last defined heating characteristic is not
changed anymore.
4
Storage tank sensor SF1/SF 2
: When one of the sensors fail, DHW heating no longer takes
place.
4
Solar circuit sensor SF2/CF
: When one of the sensors fails, the solar circuit pump is
switched off.
8.2
Collective error alarm
As an alternative to the Pump management function, a fault alarm can be indicated over the bi-
nary output BA8. Should the error status register FSr indicate a fault, the binary output BA8 is
activated.
Function
WE
Configuration
Fault alarm output BA8
OFF
FB47 = ON
64
EB 5476 EN
Operational faults