Technical data
10
Minimum evaporator water flow rates
30GH/GZ Min. flow rate, l/s
009 0.3
013 0.5
015 0.7
020 0.8
025 1.0
030 1.2
035 1.3
If the flow rate is lower, follow the recommendations below:
a. It is possible to install several chillers of lower capacity in
series, each one supplying a part of the ∆T.
b. The water from the evaporator can be recirculated, in
order to increase the flow rate. The temperature of the
mixed water entering the evaporator must be at least 2.8 K
higher than the leaving water temperature.
Maximum evaporator chilled water flow rate
This is limited by the maximum permitted evaporator pressure
drop.
30GH/GZ Max. flow rate, l/s
009 2.2
013 3.2
015 4.0
020 5.3
025 6.5
030 7.3
035 9.2
The minimum temperature difference is 2.8 K which
corresponds to a water flow rate of 0,9 l/s per kW.
Water loop volume
Whatever the size of the system, the water loop minimum
volume is given by the following formula:
Volume = CAP (kW) x N* = litres
where CAP is the nominal system capacity (kW) at the nominal
operating conditions of the installation.
Application N*
Air conditioning 3.25
Industrial process cooling 6.5
Low temperature operation 10.8
This volume is necessary for stable operation and accurate
temperature control.
It is often necessary to add a storage 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 Good
Evaporator pressure drop curve
* Application down to -18°C with head pressure control option
Note: Evaporator ∆t = 5 K
0
10
20
30
40
50
-10 -5 0 5 10 15
33
43
45
40
12
30GH 030-035
30GH 009-025
45
01
13
30GH 025
30GH 013
30GH 009
42
36
WATER
GLYCOL
30GH Operating range
STANDARD 30GH
30GH WITH LOW TEMPERATURE OPTION
Pressure drop, kPa
Water flow rate, l/s
OUTDOOR AIR TEMPERATURE, °C
EVAPORATOR LEAVING WATER TEMPERATURE, °C
*
*
GoodBad
NOTE: The compressor must not restart more than 10 times in
an hour.
30GZ Operating range
APPLICATION DATA (STANDARD UNIT)
0
10
20
30
40
50
-10 -5 0 5 10 15
39
39
40
42
43
12
30GZ009-013
30GZ009-025
45
* Application down to -18°C with head pressure control option
Note: Evaporator ∆t = 5 K
30GH/GZ 015
30GH/GZ 020
30GH/GZ 025
30GH/GZ 030
30GH/GZ 005
30GH/GZ 013
30GH /GZ 035
0.1
0.30.2 0.4 0.5 1 2 3 4 5 6 7 8 9 10
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
2
3
4
5
6
7
8
9
10
20
30
40
50
60
70
80
90
100
EVAPORATOR LEAVING WATER TEMPERATURE, °C
WATER
GLYCOL
30GZ with glycol option
CONDENSER ENTERING AIR TEMPERATURE, °C