Installation manual

16
If the system details are outside of the range shown in
the table the expansion vessel size can be calculated
using the following formula:
V = e * C / {1-[ (P
pre
+ 1)/(P
max
+ 1) ] }
Where:
e = Coefficient of Fluid Expansion with respect to 10°C
(30% Glycol/Water)
C = total System Volume (litres).
P
pre
= Pre-charge Pressure (Bar)
P
max
= Max System Pressure (Bar)
Maximum Working Temperature
30 40 50 60 70 80 90
Coefficient of Fluid Expansion with respect to 10°C (30% Glycol/
Water)
0.00272 0.00499 0.00779 0.01108 0.0148 0.01891 0.02336
Pre-charge
Pressure
(Air side of vessel)
Max System Pressure
(Pressure Relief Valve
Rating)
System
Volume
(Litres)
Approximate Expansion Vessel Volume Required (Litres) as a
Function of the Max Working Temperature
0.5 1 100 1.1 2 3.1 4.4 5.9 7.6 9.3
0.5 1.5 100 0.7 1.2 1.9 2.8 3.7 4.7 5.8
0.5 2 100 0.5 1 1.6 2.2 3 3.8 4.7
0.5 2.5 100 0.5 0.9 1.4 1.9 2.6 3.3 4.1
1 1.5 300 4.1 7.5 11.7 16.6 22.2 28.4 35
1 2 300 2.5 4.5 7 10 13.3 17 21
1 2.5 300 1.9 3.5 5.5 7.8 10.4 13.2 16.4
1 3 300 1.6 3 4.7 6.6 8.9 11.3 14
1.5 2 500 8.2 15 23.4 33.2 44.4 56.7 70.1
1.5 2.5 500 4.8 8.7 13.6 19.4 25.9 33.1 40.9
1.5 3 500 3.6 6.6 10.4 14.8 19.7 25.2 31.2
2 2.5 1000 19.1 34.9 54.5 77.5 103.6 132.4 163.5
2 3 1000 10.9 19.9 31.2 44.3 59.2 75.7 93.5
Aeromax Plus Expansion Vessel Sizing – Sizing Examples
Note: the required vessel volume will almost certainly
not correspond exactly to an existing size, therefore the
nearest available size above the value returned for V
must be selected from the available vessels in the
range.
The calculation is valid provided the expansion vessel
and the safety valve are at the same height. The
maximum system pressure for Aeromax Plus Heat
Pumps is 3 bar.
Cylinder Installation for Domestic Hot Water
We recommend the Kingspan Albion Aerocyl is used as it
has a heat pump specific coil fitted.
!
Note...
If the Aerocyl is used in conjunction with the 3 port valve
supplied with the Aeromax plus there is no requirement for
the additional 2 port valve.