Hitachi YUTAKI S COMBI Series Installation And Operation Manual page 67

7.1.0.3 Space heating pipes connection
The unit is factory supplied with two shut-down valves to be connected to the water inlet/outlet
pipe. With these shut-down valves it is very practical to connect the indoor unit to the heating
system by using the factory supplied gaskets just below the valves (2-3HP: G 1"; 4-6HP: G 1-1/4").
Then, the space heating installation can be carried out.
7.1.0.4 DHW pipes connection
The connection between the DHW installation and the DHW connections of the indoor unit must
be done taking into account the following considerations:
1 Install a pressure and temperature relief valve at the DHW inlet connec tion (as close as possible
to the tank) to provide the following functions.
• Pressure protection
• Non-return function
• Shut-down valve
• Filling
• Draining
If not, a specific device for each function should be installed.
2 Install also a shut-down valve (field supplied) in the DHW outlet connection, in order to make
easier any maintenance work.

NOTE
For more details, refer to the section
PMEN0645 rev.0 - 04/2023
Shut-off valves
Gaskets
"5.4.4.3 Additional hydraulic optional elements (For
7
DHW)".
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