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General information
EN
1.11 RESIDUAL HEAD
Available static pressure, kPa
Water flow rate, I/s
0.0
0.5
1.0
1.5
2.0
2.5
300
240
250
260
270
280
290
170
180
190
200
210
220
230
110
120
130
140
150
160
50
60
70
80
90
100
6
1
2
3
5
4
Find below the residual head curves of the pumps, for NXC/NXH units
Legend:
1. NXC 017
2. NXC 021
3. NXC 026
4. NXC 033-NXH 026
5. NXH 033
6. NXC 040-NXH 040
1.12 COOLING CIRCUIT AND PROBE POSITIONING
For NXH series units, the cooling circuit is of the heat pump
type with a refrigerant gas reversal cycle. The source fluid uti-
lized is the external air, while the utility fluid is water, with
the possible inclusion of anti-freeze liquid. During the win-
tertime, the heat pump extracts the thermal energy from the
external air and delivers it to the utility fluid, thereby hea-
ting it. During the summertime the cycle is reversed, and the
thermal energy is extracted from the water, which is cooled,
and is delivered to the external air. Based on the type of sy-
stem, the utility fluid is delivered to the fan coils, the air
treatment unit, the radiant panels for heating or cooling the
rooms, or the boiler in order to produce domestic hot water.
On the other side, NXC series units do not have the cycle re-
versal on the refrigerant gas.