TECH ST-408 User Manual

Tech

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ST-408 – user's manual

Declaration of Conformity No. 44/2011

Hereby, we declare under sole responsibility that the

ST-402 230V 50Hz thermoregulator manufactured by TECH,

headquartered in Wieprz 1047A, 34-122 Wieprz, is compliant

with the Regulation by the Ministry of Economy. (Journal of

Laws Dz.U. 155 Item 1089) of July 21, 2007 implementing

provisions of the Low Voltage Directive (LVD) 2006/95/EC of

January 16, 2007.

The ST-402 controller has been tested for electromagnetic

compatibility (EMC) with optimal loads applied.

For compliance assessment, harmonized standards were

used: PN-EN 60730-2-9:2006.

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Tech

ATTENTION!

High voltage!

Make sure the regulator is disconnected from

the mains before working on the power

supply (cable connections, device

installation, etc.)!

All connection works must only be carried

out by qualified electricians.

Before activating the controller, measure the

motor resetting efficiency and inspect wire

insulation.

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ST-408 – user's manual

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Tech

I. Application

ST-408 type thermoregulator is intended for the operation of central
heating system installation. The controller supports two mixing valves
and HUW pump (boiler pump). Optionally, controller may co-operate
with two ST-61 modules, which allows to control four mixing valves
altogether. The controller is equipped with weather control function,
weekly program, and may cooperate with two room two-state
regulators (standard) and with one TECH regulator.

An additional advantage of the device is the protection of return
temperature, which fulfills the function of protection against boiling of
the water in the short furnace circulation or against too low temperature
of the water returning to the water furnace.

II. Principle of operation

Description of control panel

Operational principle of installation controller is based on mixing the
supplying circulating warm water, with the water, which comes back from
heating circulation, in order to set the desired temperature and maintaining it
all the time at the same level.
The pump is connected to the cycle of each valve, and is supposed to help
water distribution in the system. The pump should be installed behind the
mixing valve, while the temperature sensor should be placed behind the valve
and the pump, for the purpose of the most accurate control of temperature at
valve outlet.

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PRESET

TEMPERATURE

OPENING

TEMPERATURE

BEHIND VALVE

STANDBY

MODE

(STANDBY)

PERCENTAGE

EXIT

PULSE

GENERATOR

ST-408 – user's manual

ATTENTION: if the valve controller operates, at the same time, in a
circulation common with the furnace controller, the pump can be connected
from the furnace controller (the outlet of such pumps from ST-408 type
regulator or from an additional module will remain disconnected).

The control takes place with the use of pulse generator knob. Entering
MENU and settings confirmation proceeds by pressing the knob. When turning
it, a user operates in MENU functions. To go to the higher level menu, use exit
button. Any settings may be changed in a similar manner.

II.a) Main page

During normal regulator operation , graphic display shows the
homepage, on which the following are displayed:

Valve type:

- C.H.

- FLOOR

By turning the pulse generator, the preset temperature can be easily
changed (the change is set for the currently visible main screen). After
pressing pulse generator knob, the user moves to the main menu.

To change homepage appearance for the boiler temperature view,
another valve or one of the additional valves (if active), EXIT key should be
pressed. Then, after choosing another screen, homepage view is changed.

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ACTIVE MODULES

ADDITIONAL

OPERATION MODE

VALVE PUMP

WORK

BOILER
PROTECTION

HOUR

ACTIVE

VALVE

HUW PUMP WORK

NUMBER OF THE

VALVE, THE

PARAMETERS OF

WHICH ARE

VISIBLE

ROOM CONTROL

Tech

III. Main menu

III.a) VALVE 1

In this submenu, a user sets the basic parameters of the first valve.

III.a.1) Preset temperature

With this option, the requested temperature is set, and VALVE 1 is
supposed to maintain it. The temperature can be also changed directly from
the controller main screen when Temp 1 view is active. In the course of
correct operation, water temperature behind the valve will be approaching the
preset valve value.

III.a.2) Activated

This option is used to activate valve 1. When valve is deactivated, the
pump is also deactivated. In spite of the fact that valve is deactivated,
calibration always takes place after switching the controller to the network. It
prevents from remaining valve in a dangerous position.

III.a.3) Valve calibration

Using this function, valve 1 can be calibrated at any time. During
calibration, valve is set to a safe position, that is, for CH valve, to a fully open
position, while for floor valve, to a closed position. When calibration is in
progress, the following symbol is displayed at the bottom of the main

screen:.

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ST-408 – user's manual

III.b) Valve 2

In this submenu, a user sets the basic parameters of the first valve, the same
as for valve 1 settings.

III.c) HUW pump (boiler pump)

This function is used to set HUW pump working parameters.

III.c.1) HUW preset temperature

With this function, the preset temperature of utility water is set; The
temperature can be also changed directly from controller main screen, when
HUW view is active. After heating water in the boiler up to this temperature,
the regulator deactivates HUW pump. The pump will be re-activated when the
temperature decreases below the value set by HUW hysteresis parameter
value.

III.c.2) Operational modes

This function allows for a complete deactivation of HUW pump, if it is not
used, or for the activation of automatic operation (then it works according to
the settings included in this chapter).

III.c.3) HUW hysteresis

This option is used to set the hysteresis of the preset boiler temperature.
This is a difference between the preset temperature (that is, the one required
at the boiler) and the temperature of returning to work (for example: when
the preset temperature has the value of 55°C and the hysteresis is 5°C. After
reaching the preset temperature, namely 55°C, HUW pump shuts down. HUW
pump will be re-activated when the temperature decreases to 50°C).

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Tech

III.c.4) HUW pump activation threshold

This option is used to set HUW pump activation temperature (it is the
temperature measured at the furnace sensor). The pump does not work below
the preset temperature, and above this temperature the pump is activated
and works till achieving the preset temperature.

III.c.5) Weekly regulator (weekly control of HUW pump)

This function is used for programming daily temperature changes of the
boiler. The set temperature deviations are in the range of +/-10 0C.

Operation of the weekly control is described in Chapter IV.c.16.

III.d) Circulation pump

This function is used to control the pump mixing hot water between the
furnace and the hot utility water receivers. The User, after activation of this
function, sets the daily cycle of activation or standstill of the pump with the
accuracy of 30 minutes.

To facilitate setting the daily cycle of operation and standstill of the
pump, there is a possibility to copy the selected time interval to further ones.

After setting the operation plan, it is required to set operation time and
standstill time of the pump, while the time interval selected before is active.
When necessary, it is possible to quickly remove earlier settings to facilitate
setting of new intervals.

III.e) Screen view

Using this function, homepage appearance may be changed between the
views of : basic valves, temperatures of furnace sensors, boiler temperatures
or parameters of one of the additional valves (only when the valves are
active).

After choosing the Valve screen view (1 or 2) on the website, the
following temperatures will be displayed on the homepage: valve temperature
(preset and current value) and opening percentage.

Temp 1 or Temp 2 view selection causes the display of the parameters
of the chosen valve on the homepage: the preset and the current
temperatures, external and return temperatures.

HUW view selection causes the display of the temperatures of the boiler
on the homepage: the preset and the current, external temperature and the
furnace temperature.

Additionally, after installing the additional valves, the views with their
parameters are available: the parameters of the preset and the current
temperatures, external and return temperatures, and the opening percentage
(deviation) of the chosen valve.

Screen view selection menu may be entered by pressing EXIT button,
when the main screen view is active.

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