Minimum Water Volume; Maximum Water Loop Volume (Evaporator And Condenser Side); Expansion Tank; Protection Against Cavitation (Option 116) - Carrier AquaSnap 61WG Series Installation, Operation And Maintenance Instructions

5 - APPLICATION DATA
5.6.2 - 30WG with option 6
Minimum evaporator glycol solution flow rate, l/s
30WG Minimum
Low pressure
1,4
20
1,5
25
1,5
30
1,6
35
1,7
40
1,8
45
2,5
50
2,2
60
2,2
70
2,3
80
2,5
90
2
110
2
120
2
140
2
150
2
170
2
190
(1) Option 6 : Glycol solution production, very low temperature
(2) Option 5B : Glycol solution down to 0°C
(3) Option 272 : Glycol solution down to -5°C
(4) Units with hydraulic module
Minimum flow rate for a maximum permitted temperature difference at the
minimum leaving water temperature
T Units without hydraulic module
Minimum flow rate for a maximum permitted temperature difference at the
minimum leaving water temperature

5.7 - Minimum water volume

Wichever the system, the water loop minimum capacity is given
by the table below:
61WG/30WG/30WGA size
Pure water
l
61WG/30WG/30WGA size
Pure water
l
61WG/30WG/30WGA size
Pure water
l
ATTENTION: Minimum water volume required between the unit
and possible customer-supplied valves to the outside of the unit.
Industrial process applications
Certain industrial processes may require high leaving water
stability. In these cases the values above must be increased.
It may be 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.
Bad
Bad
40
(4)
Minimum
High pressure
1,3 0,5
1,3 0,5
1,3 0,5
1,5 0,6
1,5 0,6
1,5 0,8
2,2 0,8
2,3 1,0
2,4 1,1
2,4 1,3
2,5 1,5
1,4 1,5
1,4 1,5
1,4 1,5
1,4 1,5
1,4 1,5
1,4 1,5
20 25 30 35 40
538 807 1077 1346 1615 1830
50 60 70 80
269 359 449 538
110 120 140 150 170
269 323 366 192 231
Good
Good
5.8 - Maximum water loop volume (evaporator
and condenser side)
Units with hydraulic module incorporate an expansion tank sized
T
for the maximum water loop volume.

5.9 - Expansion tank

The expansion tank is supplied with a pressure of 1 bar relative
(±20%). The maximum operating pressure for the tank is 4 bar.

5.10 - Protection against cavitation (option 116)

To ensure the durability of the pumps in the integrated hydraulic
modules, the control algorithm of the units incorporates anti-
cavitation protection.
It is therefore necessary to ensure a minimum pump entering
pressure of 60 kPa (0.6 bar) during operation and at shut-down.
A pressure below 60 kPa will prohibit unit start-up or cause an
alarm with the unit shutting down.
In order to obtain sufficient pressure, it is recommended:
- to pressurise the hydraulic circuit between 100 kPa and 300
kPa (1 and 3 bar) maximum on the suction side of the pump,
- to clean the hydraulic circuit before charging water,
- to regularly clean the screen filter.
45
90
610
190
261