
12 | EN RIS 700 V EKO 3.0 v2019.05
START/STOP feature
The operation of the recuperator is started or stoped using the START/STOP feature. “STOP” is displayed at the remote control panel (FLEX). In
START mode, the recuperator operates based on the latest settings of the panel.
FanFail and FanRun features
It provides option to connect the external fan state indication such as the indication lamp which would visualize the state of the device.
Continuous control of the heater
The new feature is installed: continuous keeping of the supply air temperature (accuracy up to 0,5 °C) by using two-way thyristor module – ESKM...
(these modules are installed only in heaters connected to the three-phase mains).
Cooling by ventilation:
Two types of cooling exist: using halocarbon or water cooler. Cooling is based on the algorithm of the PI regulator and is activated when there
is need for cooling. Conditions for activation and deactivation of halocarbon cooler can be set and changed using the menu of the FLEX remote
control panel (see section II.6.4. of the FLEX description). Actuator position of the water cooler is set accordingly to the PI regulator in the range
between 0% and 100%. The halocarbon cooler is switched on when PI regulator value exceeds the value set in the menu (see section II.6.4.2. of
the FLEX description). The halocarbon cooler is switched o when PI regulator value is less than the set value (see section II.6.4.3. of the FLEX
description).
Ventilation:
Three types of ventilation are possible (see section II.6.3. of the FLEX description): based on the supply air (Supply), based on the extracted air
(Room) and automatic (ByOutdoor). When operation is based on the supply air, the supply air temperature is maintained as set on the PI regulator.
When operation is based on the extracted air, the set extracted air temperature is maintained to keep the supplied air temperature between the
minimum and the maximum set temperatures (see sections II.6.3.2. and II.6.3.3. of the FLEX description) based on the algorithm of the PI regu-
lator. When operation is automatic (ByOutdoor), both mentioned cooling types are used (supply and extracted air): cooling based on the supply
air is used when ambient air temperature is less than the set temperature (see section II.6.3.3. of the FLEX description). This is so called “winter
mode”. Cooling based on the extracted air is used when ambient air temperature is greater than the set temperature (see section II.6.3.3. of the
FLEX description). This is so called “summer mode”.
Using the remote control panel, the user can adjust fan motor speed as three steps (values of steps are speed set in the window of the remote
control panel, see sections II.6.7 and II.6.8 of the FLEX description). Analogous 0–10 VDC control signal for motors is generated by the controller
RG1. Speed of the supply and extracted air fans can be adjusted synchronously or asynchronously (see sections II.6.7 and II.6.8 of the FLEX
description). If water supply air heater is used and after HVAC unit is switched on, fans are switched on after 20 seconds. During this period, water
valve actuator is being opened to allow water heater to reach the optimum temperature.
Two pressure converters should be used to control both fans while maintaining constant pressure at the system.
Also, CO2(extract air) converter can be connected (if no pressure converters are connected).
19.1. SYSTEM PROTECTION
a) Several steps of protection are provided for protection of the water heater.
First: if during cold periods the temperature of the outward water ow drops below +10 °C (as measured by the TV sensor), then the water heater
valve actuator M6 is forced to open regardless the need for heat.
Second: if the water temperature does not reach +10 °C after fully opening the hater valve and the air temperature after heating drops below
+7/+10 °C (as set on the protection thermostat T1), then the air supply device is stopped. To protect water heater from freezing (when the unit is
stopped), tow outputs operate: circulatory pump M4 and water heater valve actuator M6. Supply air valve actuator with the return spring is (should
be) used for the protection of the water heater. During voltage loss, supply air valve is closed immediately. It does not automatically reset and
should be reset (restarted) from the control panel.
b) When the device has the electric heater, then two levels of overheat protection are used. Two types of the capillary thermal protections are used
for the overheat protection of the electrical heater: manual and automatic. Automatic thermal protection is activated when air temperature exceeds
+50 °C and manual protection is activated when air temperature exceeds +100 °C. Automatic thermal protection +50 °C is used to disconnect the
electric heater if the temperature of the heating elements exceeds +50 °C which could cause consumption of the oxygen.
Capillary thermal protections are dierent only with respect to construction to allow automatic thermal protection to reset to the operation state.
Manual thermal protection does not reset and should be reset to the operation state by pressing RESET button on the service cover of the heater.
When manual thermal protection is triggered, fans operate in maximum capacity until the manual heater protection is reset (by pressing the reset
button) and the device is restarted. When heater fault is registered, manual heater protection can be restored only after estimation of the fault
cause and only if it is safe to do so regardless of the temperature setting on the control panel. Also it should be inspected if other automation and
installation elements are not damaged.
Antifreeze protection of the dierential pressure heat exchanger (dierential pressure relay PS600) is used only in more ecient devices (from
1200 m3/h).
Triggering of the automatic thermal protection mostly occur due to low fan speed (faulty fan, stuck/faulty air inlet valve/actuator).
19.2. USING THE UNIT IN BMS NETWORK
The recuperator can be connected to the BMS network by using the ModBus protocol.
The device can be controlled using FLEX panel and BMS network simultaneously: the device will work based on the latest changes of settings.
As set in the factory, the device will operate (if no faults are present) based on the latest panel settings in case the panel or BMS network (or even
both) is disconnected. This setting can be changed, please see Flex_meniu_montuotojas section 14 “Misc” for details.
ModBus type: RTU
RS485_2 port is used for connecting the ModBus (Fig. 3);
Settings (see section II.6.2. of the FLEX installer description):