AUKS AFC-1000CF/4, Technical Manual

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AUKS Light CAC R22 60Hz T3 Controller
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1. Precautions of product selection
a.
At given airflow and temperature of a fan coil unit, when water supply changes, so does the cooling
capacity. Based on statistics of the performance of some products, when water supply temperature is 7
℃
at 80% water supply, the cooling capacity is about 92% of the original level, indicating slow effect of the
water supply change to cooling capacity.
b. At given airflow and temperature of a fan coil unit, when water supply changes, so does the cooling
capacity. Based on statistics of the performance of some products, when water supply temperature is 7
℃
at 80% water supply, the cooling capacity is about 92% of the original level, indicating slow effect of the
water supply change to cooling capacity.
c. At given temperature difference between water supply and water return of a fan coil , the cooling
capacity decreases with as the water supply temperature increases. According to statistics, if water
supply temperature is increased by 1
℃
, the cooling capacity will decrease by about 10%, the higher the
water temperature is , the greater decrease the cooling capacity will suffer, with lowered humidity
capacity.
d. At given water supply condition, when the airflow of a fan coil changes, so do its cooling capacity and
enthalpy difference of air treatment, which usually increases as cooling capacity decreases, without much
change in power consumption of unit cooling capacity.
e. When the temperature difference between inlet and outlet water of a fan coil increases, the water flow
will decrease, so will the heat transfer coefficient of the heat exchange coil. The heat transferring
temperature will also change, as a result, the cooling capacity of a fan coil increases as the temperature
difference between supply and return water increases. According to statistics, when water supply
temperature is at 7
℃ , and the temperature difference between supply and return water has increased
from 5 ℃ to 7 ℃ , the cooling capacity may decrease about17%..
The water supply, water supply temperature, temperature difference between supply and return water ,
water flow and inlet air temperature and humidity interact with on another, with the performance of the fan
coil changed by the variation of any one of them.
f. When a fan coil runs at standard condition, the final point of air treatment depends on the enthalpy
difference of air treatment and the cooling capacity is related to the humidity load of the room, in that the
greater the heat-humidity ratio, the smaller the cooling capacity is , as shown in Figure 1. So, the air
treatment enthalpy difference of the fan coil can be determined by heat-humidity ratio curve, final point
parameters of air treatment and air parameters , and then the cooling capacity of the fan coil can be
calculated based on the air treatment enthalpy of the room at different heat-humidity ratio...