Stopping The Test; Monitoring Of Attempts; Limitations; Lwco Error Evaluated At Boiler Level - Bosch SSB1000 SA Manual

44 | System test
7 .2 .3

Stopping the test

Test OK:
The test mode is stopped when the high limit sensor of the duplex supply
sensor detects the MAX_TEMP_ERROR . The MAX_TEMP_ERROR is
stored in the boiler error history of the module,
The touchscreen shows the highest temperature of the T_Supply sensor
after the physical high limit test has been activated.
Test stopped by operator: When the test is aborted by the operator the
test mode is cleared and the override parameters are restored.
Timeout: When there is no error after 5 minutes the test stops
automatically. In this case the blocking error " HIGH_LIMIT_FAIL " is
active for 30 seconds.
7 .2 .4

Monitoring of attempts

The amount of test attempts is limited to 5 within 24hrs.
When the attempts counter > 5 the warning "high limit test wait time
active" is displayed for the module.
After 24hrs the high limit test attempts are cleared and the warning is
removed.
7 .2 .5

Limitations

The sensor temperature high limit test remains active during this test
mode. The setpoint for triggering the MAX_TEMP_ERROR lockout on
the sensor temperature is set to 115°C – 3°C hysteresis. When the
Safety Limit switch does not open during this test the sensor temperature
check stops the burner when the temperature increases to over this
setpoint. The error codes for both the Safety Limit switch and the sensor
temperature check are locking code 15, MAX_TEMP_ERROR .
When the physical high limit test is over the settings that were overruled
are restored. When the test failed the exchanger flowrate function is
still active and expects the actual flowrate to be over the minimum CH
flowrate. When this isn't true after the testing period the LOWEX_FLOW_
PROTECTION error will be stored after the HIGH_LIMIT_FAIL error is
cleared.
6720892984 (2019/02) US
7 .3

LWCO Error evaluated at Boiler level

To activate this modality set via Labvision the following parameter in the
Managing boards (Boiler X M1):
Prog. Input LWCO1: LWCO1 input (Boiler Level)
If the LWCO Error occurs in Boiler X, in case of demand request the
whole Boiler X will not start.
The Next BoilerX+1 will be then called.
BOILER 1 [M1]
M1 M2 M3
LWCO BOILER LWCO BOILER
LWCO Error!! LWCO Error!!
7 .4

System test in cascades with air damper

To enable system test a demand must be generated on the cascade
controller.
This is handled by the PB and needed because the air damper must be
opened by the cascade controller before a burner can start.
CASCADE [M1]
BOILER 2 [M1] BOILER 3 [M1]
M1 M2 M3 M1 M2 M3
LWCO
BURNER
Input ignored!
LWCO BOILER
LWCO Error!!
SSB