CLIMATIC™ 50 User manual - Lennox

2132 � CO² rate measured value of the (ppm).
3354 � CO² function authorization, adjustment by zone.
3515 � CO² function mode [0-Min], [Min-Max].
3513 � CO² rate (ppm), threshold until which the 0% or the minimum fresh air is maintained.
3514 � CO² rate (ppm), threshold from which the minimum fresh air or the 100% is used.
3512 � Maximum fresh air damper opening.
Fresh air damper Calibration
The real fresh air volume introduced into the system is not always proportional to the damper opening percentage. That
is particularly true when the return air duct system is sized to give excessive pressure losses.
It results with excessive fresh air input, and thus with an increase of the system exploitation costs. From now on, it is
possible to calibrate the fresh air using three temperature probes: one in the blowing section, another in the return air
and the last one in the outdoor temperature.
Using these three probes, Climatic50 calculates and memorizes the exact percentage of fresh air for each position of
the damper.
Blowing T° = Return T° x %Return Air + Fresh air T° x %Fresh Air
This adjustment sequence takes place periodically when all heating and cooling elements are off.
3516 � Fresh air damper calibration authorization.
FREE COOLING
From a room temperature need (Capacity Factor) the damper opens according to a proportional rule on the blowing
temperature.
0% need = Minimum fresh air.
100% need = low limit threshold (3373) + 2K
The user may choose to limit the fresh air damper operation with contacts or set points modification (see minimum fresh
air § above). The outdoor temperature or humidity value may also limit the opening.
Outdoor temperature
The Free-Cooling is stopped if the outside temperature is higher than the return or room temperature.
The Free-Cooling is stopped if the outside temperature is lower or higher than the threshold defined in set point (3511).
Free cooling is forbidden on high limit for a set point adjustment over +20.0°c.
Free cooling is forbidden on low limit for a set point adjustment lower than +20.0°c.
Outdoor humidity (optional)
If humidity control option is selected, the Free-cooling is stopped if the external absolute humidity (water weight) is
higher than the indoor absolute humidity.
Set point
The Free-Cooling is stopped if the set point (3353) is No
Free contact (optional)
Stop of Free-Cooling by closing customized free contacts. (See minimum fresh air § above)
[0% A.N.] = the register of air is completely closed.
[100% A.N.] = the register of air is completely open.
3353 � Economiser functionauthorization, adjustment by zone.
3373 � Low limit blowing temperature threshold.
3511 � Outdoor temperature threshold for authorization of the economiser function.
3512 � Maximum fresh air damper opening
CLIMATIC50 – IOM – Rooftops/ Aircoolair CL50-ROOFTOPS-IOM-1107-E 19