ensto ECO900 Instructions De Montage Et D'utilisation page 19

Alarm
SHORT HEATER
BROKEN HEATER
SHORT TEMP
BROKEN TEMP
SHORT AIR TEMP
BROKEN AIR TEMP
SHORT MOISTURE
BROKEN MOISTURE
4. Operating of the frost protection system
The heating resistor of the snow and ice sensors ECOA901 and ECOA903 keeps the surface of the sensor at a
constant temperature of approximately +4 °C. It will melt the snow and ice, which are detected as moisture.
When the temperature measured by the sensor ECOA902 or ECOA904 drops below the set value in the TEM-
PERATURE menu and the set humidity level is exceeded, the heating will turn on by closing the heater relay
(connectors 8 and 9). The heating remains on until either the set temperature is attained or the humidity level
drops below its set value.
In the post-heating the heating remains on during the selected time when either the set temperature is at-
tained or the humidity level drops below its set value. This function can be used for example if there is still
snow beside the heated area after the heating otherwise would switch off. The post-heating can be used at
temperatures below 0 °C.
The lowest operating temperature can be set between -20...-5 °C in the RANGE menu. The factory predeter-
mined value for the highest operating limit is +6 °C. Outside these temperature limits the heating can only
be switched on using the continuous heat menu item. An appropriate operating limit prevents unnecessary
energy consumption in cases there is no snow or ice in spite of frost.
In the application GROUND it is possible to set a base temperature under which the temperature of the heated
area may not drop. If the temperature drops under the base temperature, the heating will turn on irrespective
of the humidity level. The lowest operation temperature set in the RANGE menu has however priority over the
base temperature. If the base temperature is set lower than the lowest temperature limit, the base temperature
cannot be exceeded.
The ECO900 frost protection control unit is supplied with an 82 kΩ resistor connected to connectors 20 and
21 but the air temperature sensor ECOA904 can be connected instead. In this case the air temperature is also
shown on basic display mode in addition to the ground/gutter temperature and the humidity level. If the air
temperature drops rapidly, predicting the probably start of rain, the heating will switch on for one hour below
temperatures of +7 °C. Afterwards the heating will switch off or remain on depending on the set temperature
and humidity values.
Fault
Heating resistor of snow and ice sensor
ECOA901 or ECOA903 short circuit
Heating resistor of snow and ice sensor
ECOA901 or ECOA903 open circuit
Temperature sensor ECOA902 or
ECOA904 short circuit
Temperature sensor ECOA902 or
ECOA904 open circuit
Air temperature sensor ECOA904 short
circuit
Air temperature sensor ECOA904 open
circuit or 82 kΩ resistor is missing
Temperature sensor in moisture sensor
of ECOA901 or ECOA903 short circuit
Temperature sensor in moisture sensor
of ECOA901 or ECOA903 open circuit
RAK41 / 15.3.2022
Wire color Connectors
green / brown 12 / 14
green / brown 12 / 14
yellow / brown or 18 / 19
blue / brown
yellow / brown or 18 / 19
blue / brown
brown / blue 20 / 21
brown / blue 20 / 21
yellow / brown 13 / 14
yellow / brown 13 / 14
19 / 56