TECH EU-391 ZPID, User Manual

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VI.b) Fire-up (Throttle ON/OFF)
The aim of this function is to achieve optimum fl ame in the shortest time possible.The fi re-
up eff ectiveness is enhanced by throttle operation. This phase lasts until CH temperature
reaches a pre-defi ned value required to enter the operation mode.
Once the controller enters operation mode, instead of Fire-up function, Throttle ON/OFF
appears in the menu. The throttle may be disabled if necessary (e.g. while adding fuel)
- then the throttle closes completely. Damping process may also be initiated by disabling
the throttle.
VI.c) Manual mode
The regulator off ers manual mode function. In this function, each executive device may
be activated and deactivated independently of others ( CH pump, voltage-free contact,
additional pump, buff er pump). Additionally, the throttle position may be adjusted manually
by changing the degree of opening in percentages. The throttle will start changing its
position about 2 seconds after the change has been introduced.
VI.d) Operation modes
This function is used to select the operation mode of the
pump.
NOTE:
Water tank priority mode is available only for DHW
pump (see: Additional pump settings submenu).
VI.d.1) Only CH pump
When this function is selected, the controller enters house
heating mode and controls only the CH pump (additional
pump is inactive). CH pump is activated when the temperature is above the pump activation
threshold (factory setting: 300C). Below this temperature value (minus hysteresis) the
pump is disabled.
VI.d.2) Parallel pumps
In this mode the pumps are enabled above the pump activation temperature measured by
CH sensor. The temperature values may diff er depending on pre-set parameters. It may
result in diff erent activation times, but when the temperature exceeds both these threshold
values, both pumps will be active. CH pump operates all the time and additional pump is
enabled when its activation conditions are met.
VI.d.3) Water tank priority
This function is available only when DHW pump is selected as additional pump.
When the pre-set DHW temperature has been reached, DHW pump is switched off and the
CH pump is activated.
CH pump operates continuously until the water tank temperature drops below the pre-
set value minus DHW hysteresis. Then, the CH pump is disabled and the DHW pump
is activated (in this mode the pumps operate alternately). This mode involves heating
domestic hot water before heating water in the radiators.
WARNING
Return valves should be installed on the circuits of the CH and DHW pumps. The
valve on DHW pump prevents hot water from being sucked out of the water tank.
The valve on the CH pump circuit prevents the hot water heating the water tank
from passing to the house heating installation.
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EU-391 z PID