Carrier 30KAV-ZE Series - Water Flow Evaporator Bypass; Variable Flow Evaporator; Minimum System Water Volume

4.8 - Water ow evaporator bypass
If the installation ow rate exceeds the maximum unit ow rate, it
can be bypassed as shown in the diagram.
For maximum chilled water ow rate
B
C
Legend:
B
Evaporator
C
Bypass
4.9 - Variable ow evaporator
Variable evaporator ow can be used in standard chillers. The ow
rate must be higher than the minimum ow given in the table of
permissible flow rates and must not vary by more than
10% per minute.
If the ow rate changes more rapidly, the system should contain
a minimum of 6.5 litres of water per kW instead of 3.25 l/kW.
The ow rate can also be controlled by the unit via option 299:
Checking the variable water ow rate.
This option allows the unit to control an external pump in order to
maintain a constant inlet/outlet temperature di󰀨erence, a constant
outlet pressure or an unoccupied mode.
4.10 - Minimum system water volume
Regardless of the system, the water loop minimum volume is given
by the formula:
Volume [L] = Capacity [kW] x N
Where Capacity is the nominal system cooling capacity (kW) at
the nominal operating conditions of the installation and N is the
quantity of Liters per kW for the water loop, as follows :
Application N
Normal air conditioning 3,25
Process type cooling 6,5
This volume is necessary for stable operation.
It may be necessary to add a bu󰀨er water tank to the circuit in
order to achieve the required volume. The tank must itself be
internally ba󰀪ed in order to ensure proper mixing of the liquid
(water or brine). Please refer to the examples below.
Connection to a bu󰀨er tank
Incorrect
Incorrect
Correct
Correct
4 - WATER CONNECTIONS
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