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Installation, operation and maintenance instructions - VMGFE102
This fl ow rate variation is realised, observing the minimum
and maximum admissible unit fl ow rates as well as the
minimum and maximum pump supply frequency values.
The delta T value maintained can in certain cases be diff erent
from the set point value:
•
If the set point value is too high (achieved for a lower
fl ow rate than the minimum value or a lower frequency
than the minimum value), the system settles at the
minimum fl ow rate or minimum frequency and this
results in a lower delta T value than the set point.
•
If the set point value is too low (achieved for a higher
fl ow rate that the maximum value or a higher frequency
than the maximum value), the system settles at the
maximum fl ow rate or maximum frequency and this
results in a higher delta T value than the set point.
Hydronic circuit cleaning procedure
Please refer to the hydronic circuit cleaning procedure
described in chapter 12.3.
Delta T set point control procedure
Once the circuit has been cleaned, stop the forced operation of
the pump and proceed with the confi guration of the unit for
the required control mode (consult the control manual).
There is no particular control, except the control used for the
unit control parameters of the delta T to be controlled.
Adjust the control parameters (refer to the control manual):
• Water
fl ow rate control method (delta T)
•
Delta T value to be controlled
The unit default confi guration is fi xed speed, 50 Hz.
