0906-E
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Moreover, the (3326) set point limits the power factory in cooling mode, and the (3336) set point limits the power
factory in heating mode.
The control calculates the difference between the Inlet and Outlet water temperature.
Example:
For a unit with two screw compressors, with six steps (16.6% by stage); if the (3326) set point is equal to 5°C, then
5 / 6 = 0.8°C
And if the chilled water supply temperature set point is equals to 7°C the power factory can go up to the 16.6% (1
stage) only if (T.Inlet - T.Outlet) > 0.8°C
Then the power factory can go up to the 32.2% (2 stages) only if (T.Inlet - T.Outlet) > 1.6K, and so…