
59
HYDRAULIC CONNECTION FOR INDOOR UNIT
ENGLISH
Setting the pressure for the expansion vessel for DHW
• For proper operation of the expansion vessel, a suitable setting of the vessels operating
pressure must be made. The pressure is set in regards to the pressure in the DHW system.
The setting needs to be checked every 12 months.
• Expansion vessel for DHW is factory filled to a precharge pressure p
0
with dry nitrogen. The
pressure must be set depending on the settings of the pressure reducing valve on the DHW
supply to the building.
• The pressure in the expansion vessel must be set according to the following formula:
p
0
= p
rv
− 0,2 bar
p
0
– pressure in the expansion vessel
p
rv
– setting of the pressure reducing valve
NOTE
• The cold DHW connection must be fitted with an expansion vessel suitable for drinking
water. The selection and installation must be in accordance with the standard DIN 4807 T5.
• An expansion vessel of 8 l volume – that can be integrated into the unit - is available as
accessory.
• The actual size of the vessel must be decided by the installer. If a larger volume is needed,
a third-party expansion vessel must be installed outside of the unit.