Daikin EPRA18DAV3 - Piping Installation; Preparing Water Piping; Water Circuit Requirements

7 | Piping installation
Installer reference guide
73
EPRA14~18DAV3+W1 + ETVH/X16S18+23DA6V+9W(G)
Daikin Altherma 3 H HT F
4P587502-1B – 2020.12
7 Piping installation
In this chapter
7.1 Preparing water piping ........................................................................................................................................................... 73
7.1.1 Water circuit requirements ................................................................................................................................... 73
7.1.2 Formula to calculate the expansion vessel pre-pressure...................................................................................... 75
7.1.3 To check the water volume and flow rate............................................................................................................. 75
7.1.4 Changing the pre-pressure of the expansion vessel ............................................................................................. 78
7.1.5 To check the water volume: Examples .................................................................................................................. 78
7.2 Connecting water piping ........................................................................................................................................................ 79
7.2.1 About connecting the water piping ....................................................................................................................... 79
7.2.2 Precautions when connecting the water piping.................................................................................................... 79
7.2.3 To connect the water piping.................................................................................................................................. 79
7.2.4 To connect the recirculation piping....................................................................................................................... 82
7.2.5 To fill the water circuit ........................................................................................................................................... 82
7.2.6 To protect the water circuit against freezing ........................................................................................................ 82
7.2.7 To fill the domestic hot water tank........................................................................................................................ 85
7.2.8 To insulate the water piping .................................................................................................................................. 86
7.1 Preparing water piping
7.1.1 Water circuit requirements
INFORMATION
Also read the precautions and requirements in the "1 General safety
precautions"[46].
NOTICE
In case of plastic pipes, make sure they are fully oxygen diffusion tight according to
DIN4726. The diffusion of oxygen into the piping can lead to excessive corrosion.
▪ Connecting piping – Legislation. Make all piping connections in accordance with
the applicable legislation and the instructions in the "Installation" chapter,
respecting the water inlet and outlet.
▪ Connecting piping – Force. Do NOT use excessive force when connecting the
piping. Deformation of the piping can cause malfunctioning of the unit.
▪ Connecting piping – Tools. Only use appropriate tooling to handle brass, which is
a soft material. If NOT, pipes will get damaged.
▪ Connecting piping – Air, moisture, dust. If air, moisture or dust gets into the
circuit, problems may occur. To prevent this:
- Only use clean pipes
- Hold the pipe end downwards when removing burrs.
- Cover the pipe end when inserting it through a wall, to prevent dust and/or
particles from entering the pipe.
- Use a decent thread sealant to seal connections.
▪ Insulation. Insulate up to the base of the heat exchanger.
▪ Freeze. Protect against freezing.
▪ Closed circuit. Use the indoor unit ONLY in a closed water system. Using the
system in an open water system will lead to excessive corrosion.