Technical data
10. MINIMUM AND MAXIMUM SYSTEM WATER CONTENT
Minimum system water content
The minimum water content for the system shown in table 1 allows the number of compressor starts and stops to be limited.
Expansion vessel calibration
The expansion vessels are pre-charged to a standard pressure
of 1 bar.
The pre-charge pressure is chosen depending on the maximum
difference in height between the system terminal and the heat
pump, as shown in the figure.
The maximum height must not exceed 55 metres due to the
maximum vessel pre-charge pressure of 6 bars.
Make sure that the system terminal at the lowest point H1 can
withstand the pressure of the water column at that point.
H
H1
Maximum system water content
The heat pumps are fitted as standard with an expansion vessel and safety valve. The maximum system water content depends on the
capacity of the expansion vessel (see table 2) and the calibration of the safety valve (see table 3).
Table 4 shows an example of the maximum water content in the specified normal operating conditions.
If the volume of water in the system is higher, an additional, correctly sized expansion vessel is required.
The data shown in the table refer to heat pumps with a 2-litre expansion vessel and a minimum water temperature of 4°C
Tab. 1
Size 0011 0025 0031 0041 0061 0071 0091 0101 0121
Minimum water content l 27 37 44 56 80 100 115 130 170
Tab. 2
Size 0011 0025 0031 0041 0061 0071 0091 0101 0121
Expansion vessel l 2 2 2 2 5 5 5 8 8
Tab. 3
Size 0011 0025 0031 0041 0061 0071 0091 0101 0121
Safety valve bar 6 6 6 6 6 6 6 6 6
Tab. 4
System water temperature °C 20
Hydraulic head m 30 25 20 15 >12,25
Expansion vessel pre-charge bar 3,2 2,8 2,3 1,8 1,5
Maximum water content l 435 515 595 670 715
System water temperature °C 35
Hydraulic head m 30 25 20 15 >12,25
Expansion vessel pre-charge bar 3,2 2,8 2,3 1,8 1,5
Maximum water content l 135 160 180 205 220
System water temperature °C 45
Hydraulic head m 30 25 20 15 >12,25
Expansion vessel pre-charge bar 3,2 2,8 2,3 1,8 1,5
Maximum water content l 80 95 110 120 130
System water temperature °C 55
Hydraulic head m 30 25 20 15 >12,25
Expansion vessel pre-charge bar 3,2 2,8 2,3 1,8 1,5
Maximum water content l 55 65 75 85 90
BWR MTD2
HFC 410ABWR_MTD2_0011_0121_201110_EN
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