Caladair EVERSKY 500 Installation And Commissioning Manual page 34

When the measured CO2 level is:
- Less than 800ppm (adjustable) the fan speed set is equal to the minimum set point (= reduced speed)
- Greater than 1000ppm (adjustable) the fan speed set is equal to the maximum set point (= normal speed)
- Between 800 and 1000ppm, the fan speed setpoint is calculated in relation to the line that passes through the 2 points.
Recommendation to adjust the low CO2 threshold:
Ambient air contains a variable share of CO2 depending on where you are located. This concentration is usually always above
300ppm for an extra-urban location and can exceed 700ppm for a very dense urban location. An increase in the speed of the fans
and therefore in the air flow will in no way lower the concentration of CO2 in the room below this "base" value.
It is therefore advisable not to set the CO2 threshold for the reduced speed too far below the basic CO2 concentration of the
outside air, in order not to generate unnecessary air exchange, which leads to energy consumption and noise pollution.
Recommendation to adjust the high CO2 threshold:
The level of CO2 in the supply air has a direct impact on the comfort and well-being of the occupants. Repeated and prolonged
exposure to CO2 concentration values above 1000ppm can have adverse effects on the human body. This value of 1000ppm will
therefore be kept as a reference for the CO2 threshold setting for normal speed.
If the unit is equipped with a heating coil to provide all the heating requirements, it may be advisable to increase the ventilation
setpoints of reduced speed (in particular) and normal speed to maintain the room temperature if the heat losses of the room require
it.
When the high threshold of CO2 (1000ppm) cannot be maintained, especially in case of high occupancy of the room, it may be
necessary to increase the normal speed setpoint.
In the event that the unit is not equipped with a heating coil, the reduced speed setpoint may be reduced without being less than
30% in order to ensure:
- Evacuation of residual moisture from the room
- Proper operation of the supply and extract air fans as well as their operating control device (DEP S and DEP R).
MS-CDF-019 – Manufacturing Nr: 220001→
EVERSKY
Version B Update: 2022/06/14
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