18 | Troubleshooting
4.5
Cascade settings menu
When a cascade module is installed, the menu Service menu > Cascade
settings is displayed on the user interface (not available for all user
interfaces). When this menu is not available in the installed user
interface, the cascade module uses default settings. These settings can
be changed with an appropriate user interface even when the user
interface is only temporarily connected.
Menu item
Adjustment range
Offset header sensor
– 20 ... 0 ... 20 K
Set temp. cascade max
30 – 90 °C
Casc. pump overrun time
0 ... 3 ... 15 min
Flow temp. peak load
30 ... 50 ... 70 °C
Outside temp. Peak load
– 20 ... 10 ... 20 °C In the control strategy "Serial cascade with peak load coverage" (coding card at position 3), the heat source
Start-up delay Next device
0 ... 6 ... 30 min
Tolerated over temp.
0 ... 5 ... 10 K
Tolerated under temp.
0 ... 5 ... 10 K
Table 6
4.6
Diagnosis menu
The menus depend on the installed user interface and system design.
Solar
If an MC 400 module is installed, the Solar > Cascade menu is
displayed.
This menu allows you to call up information on the current status of the
system and the individual devices in the cascade. For example, you can
display the level of the system's flow and return temperature, or the
current appliance output.
If an MC 400 module is installed, the menu Solar > System
information > Cascade is displayed.
This menu allows you to call up information on the MC 400 module
(cascade module type, cascade module software version) and the
individual devices in the cascade (such as control device 1 type,
control unit 1 software version).
The information and values that are provided depend on the system that
has been installed. Observe the documents for the heat source, user
interface, additional modules and other system components.
6 720 809 453 (2014/12)
Function description
The flow temperature demanded by the control is changed by this value.
Maximum flow temperature of the cascade at the low loss header.
The over-run time for the heating pump (secondary side) connected to the cascade module. Over-run will operate
the pump after the heat demand is satisfied.
In the control strategy "Serial cascade with peak load coverage" (coding card at position 3), the heat source
necessary to cover the peak load is connected when the flow temperature required by the controls exceeds the
value set here.
necessary to cover the peak load is connected when the outside temperature falls below the value set here.
Once a heat source is connected, the controls wait for the time set here until the next device is connected.
To reduce the device cycles, the heat sources are only turned off when the flow temperature exceeds the desired
set temperature by the tolerated over temperature (positive switching differential).
To reduce the device cycles, the heat sources are only turned on when the flow temperature falls below the desired
set temperature by the tolerated under temperature (negative switching differential).
5
The indicator shows the operating condition of the module.
The default settings are shown in bold in the adjustment
ranges.
Troubleshooting
Only use original spare parts. Any damage resulting from
spare parts that are not supplied by the manufacturer is
excluded from liability.
If a fault cannot be rectified, please contact Worcester's
Technical Helpline.
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6 720 647 922-52.1O
MC 400