Tech Controllers ST-979 User Manual

TECH
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 Hysteresis
This option is used to define the hysteresis of the pre-set temperature.
When the pre-set temperature is reached, the pump is switched off. It is switched on again when
the temperature on the sensor drops below the pre-set value minus hysteresis.
For example, if the pre-set temperature is 60°C and the hysteresis value is 3 °C, the DHW pump
is switched off when the set temperature of 60°C is reached, and it is activated again when the
temperature drops to 57 °C.
 Pre-set temperature
This option is used to set the pre-set temperature of the device. When the temperature is reached,
the device is switched off. The temperature is measured by sensor 2.
 Maximum temperature
This option is used to set the maximum temperature of sensor 1 (it reads the temperature from
the heat source). When the temperature is reached, the device is switched on regardless of the
current temperature on the sensor 2. It protects the installation against overheating.
 Sensor 1 selection
This option is used to select which temperature sensor should be used to provide data for
controlling the operation of the device connected to the additional contact – the heat source
(activation threshold).
 Sensor 2 selection
This option is used to select which temperature sensor should be used to provide data for
controlling the operation of the device connected to the additional contact – (pre-set
temperature).
VI.b.3) Circulating pump
Once this option is selected, the additional pump serves as the circulating pump. The pump
controls the valve which mixes the hot water between the CH boiler and the DHW receivers. The
following parameters need to be configured for the circulating pump to work correctly:
 Operation time
This parameter defines the time of pump operation during its activity.
 Pause time
This parameter defines the frequency at which the circulating pump is enabled during its activity.
 Operation schedule
The user may program a daily schedule of pump operation and inactivity, with the accuracy of 30
minutes. The pump is enabled at the frequency defined in Pause time parameter and remains
active for the time defined as Operation time. For the user’s convenience, it is possible to copy a
given time setting.
VI.b.4) Floor pump
Once this option is selected, the additional device serves as a floor pump controlling the underfloor
heating pump. The following parameters are used to configure the pump operation:
 Pump switch on temperature
This parameter defines the temperature of floor pump activation (temperature read from sensor
1).
 Maximum temperature
This parameter defines the temperature of pump deactivation (temperature read from sensor 2).
 Floor sensor
This function is used to select the sensor which will provide data for floor pump deactivation (it
concerns Maximum temperature parameter).

Tech Controllers ST-979 Specifications

General

Brand	Tech Controllers
Model	ST-979
Category	Controller
Language	English