Water Piping; Domestic Hot Water Hydraulic Circuit; Hydraulic Circuit - Hitachi YUTAKI S80 Series Installation And Operation Manual

WATER PIPING

5 WATER PIPING

5.1 DOMESTIC HOT WATER HYDRAULIC CIRCUIT

5.1.1 Hydraulic circuit

Nature No.
1 Security water valve unit (DHWT-SWG-01)
Accessories
2 Water check valve (ATW-WCV-01)
3 Recirculation pump
Field
4 Shutoff valve
supplied
5 Drain
6 Heating coil
7 Heating coil outlet water pipe (accessory)
Factory
8 Heating coil inlet water pipe (accessory)
supplied
9 DHW outlet water pipe (accessory)
10 DHW inlet water pipe (accessory)
Water flow
(Security valve detail)
Check valve
Shut-off valve
Main DHW
inlet
Pressure relief valve

Hydraulic necessary elements
The next hydraulic elements are necessary to correctly perform
the domestic hot water circuit:
1 Security water valve (DHWT-SWG-01 accessory): this
•
Hitachi accessory (1) is a pressure and temperature relief
valve that must be installed as near as possible at the DHW
inlet connection before the DHW inlet water pipe factory sup-
plied (10) (pressure setting 7 bar. The security water valve
provides:
- Pressure protection
Non-return function
-
Shut-off valve
-
- Filling and emptying functions
- Draining
Ref.
Main inlet water (DHW inlet)

DHW inlet connection

Pressure relief valve and manual empty

Emptying connection (drain pipe)

Water check valve (non return)

Shut-off valve

18
Part name
Union Nut
Heating coil inlet
(From the indoor unit)
Main DHW
inlet
Draining
Name
PMML0291A rev.2 - 09/2014
Optional recirculation
Security water valve
(DHWT-SWG-01)
1
N O T E
The discharge pipe should be always open to the atmosphere,
free of frost and in continuous slope to the down side in case that
water leakage exists.
• 1 Shut-off valve (field supplied): one (4) must be connected
after the DHW outlet water pipe factory supplied (9) in order to
make easier any maintenance work.
DHW Tank
Heating coil outlet
(To the indoor unit)
DHW
2
5
6
3
4