Additional Hydraulic Necessary Elements For Dhw - Hitachi YUTAKI S COMBI Series Installation And Operation Manual

The following hydraulic elements are necessary to correctly perform the space heating water circuit:
• Two shut-down valves (factory supplied accessory) (3) must be installed in the indoor unit. One
at the water inlet connection (1) and the other at the water outlet connection (2) in order to
make easier any maintenance work.
• A water check valve (ATW-WCV-01 accessory) (4) with 1 shut-down valve (field supplied) (5)
must be connected to the water filling point when filling the indoor unit. The check valve acts as
a safety device to protect the installation against back pressure, back flow and back syphon of
non-potable water into drinking water supply net.
5.4.4.2 Additional hydraulic necessary elements for DHW
YUTAKI S Combi is factory-supplied ready for DHW operation (Fitted with DHW tank and 3-way
valve). Only the following elements are required in the DHW circuit:
Nature
Piping connections
Field supplied
• 1 Shut-down valve (field supplied): one shut-down valve (4) must be connected after the DHW
water outlet connection of the DHW tank (2) in order to make easier any maintenance work.
• A Security water valve (Field-supplied): this accessory (3) is a pressure and temperature relief
valve that must be installed as near as possible to the DHW water inlet connection of the DHW
tank (1). It should ensure a correct draining (5) for the discharge valve of this valve. This security
water valve should provide the following:
PMEN0645 rev.0 - 04/2023
DHW TANK
No.
1 Water inlet (DHW)
2 Water outlet (DHW)
Pressure and temperature relief valve
3a Shut-off valve
3
3b Water check valve
3c Pressure relief valve
4 Shut-off valve
5 Draining
Part name
5
30