Bosch HPC 410 Installation Instructions For Contractors page 19

Table 33
A51 - 6021 - [Solar collector temperature sensor defective]
Test procedure/Cause
Check configuration. The selected
setting requires a solar collector
temperature sensor
Check connecting lead between
solar module and collector
temperature sensor
Check collector temperature
sensor according to the table
Check the voltage at the terminals
of the collector temperature
sensor on the solar module
according to the table
Table 34
A51 - 6022 - [Cylinder 1 Bottom temp. sensor faulty - heating
standby mode active]
Test procedure/Cause
Check configuration. The selected
setting requires a bottom cylinder
temperature sensor.
Check connecting lead between
solar module and bottom cylinder
temperature sensor
Check the electrical connection of
the connecting lead at the solar
module
Check the bottom cylinder
temperature sensor according to
the table
Check the voltage at the terminals
of the bottom cylinder
temperature sensor on the solar
module according to the table
Table 35
A61...A64 – 1081...1084 – [two master control units in the
system] (A61/1081 = heating circuit 1...A64/1084 = heating
circuit 4)
Test procedure/Cause
Check parameter settings at the
installation level
Table 36
Hxx - ... - [...]
Test procedure/Cause
For instance, service interval of
heat source elapsed.
Table 37
A01 - 5378 - [Outdoor unit defrost failure]
Test procedure/Cause
Too low temperature of heating
system.
Defective sensor TL2.
Table 38
HPC 410 – 6721832682 (2021/02)
Action
Change configuration.
Establish a connection properly
If values do not match, replace the
sensor
If the sensor values matched, but
the voltage values do not, replace
the solar module
Action
Change configuration
Establish a connection properly
If a screw or plug is loose, rectify
the contact problem
If values do not match, replace the
sensor
If the sensor values matched, but
the voltage values do not match,
replace the module
Action
Register room temperature-
dependent controller for heating
circuit 1... 4 as remote control
Action
Service required; see documents
for the heat source.
Action
Open more thermostats on the
heating system.
Check sensor TL2 against sensor
tables. Replace sensor TL2 If there
is a deviation.
A01 - 5522 - [Wrong combination of indoor and outdoor units]
Test procedure/Cause
Not matching combination of heat
pump and indoor unit.
I/O module in the heat pump has
been replaced, but the rotary
encoder is not correctly set.
Installer module in the indoor unit
has been replaced, but the rotary
encoder is not correctly set.
Table 39
H01 - 5594 - [Air in the system]
Test procedure/Cause
Heat carrier flow blocked by a
valve.
No heat carrier flow due to faulty
primary circulation pump.
Air in the appliance.
Table 40
H01 - 5239 - [DHW temp sensor TW1 fault]
Test procedure/Cause
Sensor TW1 / signal cable shorted
or broken.
Defective installer board.
Table 41
Unit troubleshooting
Action
Check if the combination is
allowed against combination
tables.
Check rotary encoder setting on
the old I/O module or in the
electrical wiring diagram.
Check rotary encoder setting on
the old installer module or in the
electrical wiring diagram.
Action
Open all valves blocking the flow.
Check the primary DHW circulation
pump and replace it if faulty.
Perform purging procedure
according to the installation
instructions of the appliance.
Action
With the sensor disconnected from
the installer board, measure and
compare the resistance to the
sensor table. Repair cable or
replace sensor if is deviation
found.
If the sensor is working correctly
and the warning still triggered,
replace the installer board.
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