Swegon BlueBox Zeta Rev Series Installation, Use And Maintenance Manual page 59

7.3.2.1 Setting the operating setpoint difference
The units are shipped from the factory with a setpoint difference value of 5°C.
The procedure below explains how to edit the factory value.
- go to the main screen and press the arrow right button;
- click the arrow down button to select the "Flowzer" function and then press "Enter" to confirm;
- Press the button "SET" to access the screen where the setpoint difference value is set up: use the "arrow" buttons to
move and select the parameter to be edited.
- Press "ENTER" to enable the edit window.
- Use the "arrow" buttons to set the new value and press "ENTER" to confirm.
Check that the flow rate through the heat exchanger in the unit, including without thermal load, is within the
operating limits admitted in the technical catalogue.
7.3.2.2 System type 2
This system consists of a primary and a secondary circuit and it is also fitted with a hydraulic circuit breaker to make up for
any difference in flow rate between the two circuits.
The controller modulates the speed of the pump in the primary circuit in order to keep constant the temperature difference
between the unit inlet and outlet. Additionally, it provides for the correct water flow rate at all times by reading the pressure
difference on the evaporator.
A sample diagram is shown below.
A2
UL
The abbreviations present in the diagram indicate:
- A2 = cooling unit controller
- BT1 = unit input temperature sensor
- BT2 = unit output temperature sensor
- EU = heat exchanger in cooling unit
- BP41= differential pressure sensor;
- ΔPex = pressure difference at the ends of the unit;
- VPP = variable flow pump in primary circuit;
- VPS = variable flow pump in secondary circuit;
- U1, U2 .. Un = points of use present in the system/plant
- Y2V = 2-way valve servo controls
- Y3V = 3-way valve servo controls
We reserve the right to make changes without any prior notice.
BT2
BP41
ΔPex
BT1
VPP
VSP
Vmin.
Y2V Y2V
Translation from original instructions
Y3V
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