© Austria Email AG
19
V1.0 1/2021
Expansion vessel dimensioning:
Safety valve setting [bar]
6
10
System pressure [bar]
3,0
3,5
4,0
3,0
3,5
4,0
Water heater volume [L]
Expansion vessel [L]
450
24
32
44
15
16
17
*This is only a recommendation. The exact size of the expansion vessel must be determined by the
installer/project designer according to the size of the system to which the vessel will be installed.
5.5.2
Connection of the Air Duct System
A heat pump with air-duct system enables the following:
•
placement in any room large enough for the installation of the device,
•
ventilation of a selected room,
•
discharge of waste air or supply of fresh air from the outside.
The air duct system should be executed in such a way, that it minimizes the change of the air flow
direction. The distance between the point of air intake and the point of air discharge should not exceed
10 m. Frequent change of the air flow direction is regarded as additional air resistance, which means
that the length must be shortened. Each additional 90
°
pipe elbow shortens the overall length by 0,5
m. Closure elements (grates, filters, ventilation valves, etc.) in the air duct system must be taken into
account as well. Increased pressure drop in the duct system reduces the air flow. If the air temperature
is below +10
°
C, this can cause a slow freezing of the evaporator and thus less efficient ventilation,
which is difficult to notice.
NOTE
It is necessary to install at least one 90
°
pipe elbow in order to prevent the inlet
and outlet air to mix.
Figure below illustrates the heat pump cover with nozzles for air ducts, which are 45 mm high with an
external diameter of
Φ
150. Access to the internal parts is covered with a protective grid, which must
not be removed.
