CIAT AirCompact Control, Руководство по управлению

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18
1.6.10
Free cooling
The aim of this function is to make use of fresh outdoor air before starting to use the cooling coil to cool the building's supply air.
This function is only available if there is a mixing box or a plate heat exchanger equipped with a bypass damper.
Free Cooling management is based on actuating the mixing damper servomotor to alter the proportion of fresh air brought into the
building and opening the plate heat exchanger bypass, if present.
To authorise Free cooling, certain conditions must be fulfilled:
-
The fresh air temperature must be below 17°C.
-
The fresh air temperature must be below the return (or ambient) air temperature – 3°K
If there is a mixing damper, the percentage of fresh air depends on the cooling request sent by the regulation. A minimum value of
fresh air supply when the unit is stopped is adjustable.
1.6.11
Humidifier
Humidification of the intake air is managed via a self-contained humidifier equipped with a humidity sensor and authorised to
operate in accordance with the order given by the controller once the unit is running at optimum levels.
A summary of faults will be sent back to the controller via a potential-free (dry) contact so an alarm is displayed.
1.6.12
CO
2
air quality
The aim is to regulate the air quality, measured in ppm of CO
2
, using a duct sensor measuring the return flow, the measurement
range for which is 0 to 2000ppm.
There are two possible actions to manage the air quality, which can be combined:
-
Either the mixing damper is managed to alter the proportion of fresh air supplied to the building
-
Or the fan flow rate is varied
In the event that the two actions are selected, the controller will actuate the mixing damper, then alter the fan flow rate.
This management is incompatible with pressure regulation in the supply air duct.
SMR
ppm CO
2
900
8500
800
Quality proportional band
setpoint