Tech Controllers ST-976 User Manual page 33

Maximum temperature
The user defines the minimum acceptable CH temperature at which the valve will close.
Return protection
BUILT‐IN
VALVE /
ADDITIONAL
VALVE 1, 2
This function allows setting up CH boiler protection against too cool water returning from the main circulation,
which could cause low‐temperature boiler corrosion. The return protection involves closing the valve when
the temperature is too low, until the short circulation of the boiler reaches the appropriate temperature.
Minimum return temperature
The user defines the minimum acceptable return temperature at which the valve will close.
Valve pump
BUILT‐IN
VALVE /
ADDITIONAL
VALVE 1, 2
This option enables the user to select the pump operation mode:
o Always ON ‐ the pump operates all the time, regardless of temperatures.
o Always OFF ‐ the pump is permanently deactivated and the regulator controls only valve operation
o ON above threshold ‐ the pump is activated above the pre‐set switch‐on temperature. If the pump
is to be activated above the threshold, the user should also define the pump switch on temperature.
The temperature is read from CH sensor.
Factory settings
This function enables the user to restore the factory settings for a particular valve. Restoring factory settings
does not change the type of valve selected (CH or floor).
Valve removal
NOTE
This option is available only for an additional valve (using an external module).
This option is used to remove the valve from the controller memory. Valve removal is used e.g. at
disassembling the valve or module replacement (re‐registration of a new module is necessary).
OFF
ON
Minimum return temperature
Always ON
Always OFF
ON above threshold
Pump switch on temperature
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