Hitachi YUTAKI S COMBI Serie Manuel D'utilisation page 20

REFRIGERANT AND WATER PIPING
4.3 SPACE HEATING AND DHW
!
D A N G E R
Do not connect the power supply to the indoor unit prior to filling the space heating and DHW circuit with water and checking water pressure
and the total absence of any water leakage.
4.3.1 Additional hydraulic necessary elements for space heating
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.
4.3.2 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:
• 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:
- Pressure protection
Non-return function
-
- Shut-down valve
?
N O T E
The discharge pipe should always be open to the atmosphere, free of frost and in continuous slope to the down side in case that water leakage exists.
10 PMML0338B rev.1 - 03/2016
Nature Nº
1 Water inlet (Space heating)
Piping connections
2 Water outlet (Space heating)
Factory supplied 3 Shut-down valve (factory-supplied)
Water check valve
Accessories 4
(ATW-WCV-01 accessory)
Field supplied 5 Shut-down valve
Nature Nº
1
Piping connections
2
3
Field supplied
4
5
- Filling
Draining
-
Part name
Part name
Water inlet (DHW)
Water outlet (DHW)
Pressure and temperature relief valve
3a Shut-down valve
3b Water check valve
3c Pressure relief valve
Shut-down valve
Draining