Variable Flow Evaporator; System Minimum Water Volume - Carrier AquaForce PUREtec 61XWHLZE 03 Installation, Operation And Maintenance Manual

6 - APPLICATION DATA

6.7 - Variable flow evaporator

Variable evaporator flow can be used. The controlled flow rate
must be higher than the minimum flow given in the table of
permissible flow rates and must not vary by more than 10% per
minute.
If the flow rate changes more rapidly, the system should contain a
minimum of 6.5 liters of water per kW instead of 3.25 l/kW.

6.8 - System minimum water volume

Whichever the system, the water loop minimum volume is given
by the formula:
Volume = Cap (kW) x N litres
Application
Normal air conditioning
Process type cooling
where Cap is the nominal system heating capacity (kW) at the
nominal operating conditions of the installation.
This volume is necessary for stable operation. It is often necessary
to add a buffer water tank to the circuit in order to achieve the
required volume. The tank must itself be internally baffled in order
to ensure proper mixing of the liquid (water or brine). Refer to the
examples below.
Conection to buffer tank
Bad
Bad
N
3,25
6,5
Good
Good
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