Hitachi YUTAKI S Series Technical Catalogue page 124

9 Electrical and control settings
Optional indoor unit wiring (accessories)
Mark Part name
28
YUTAKI M: Auxiliary power
YUTAKI S / S COMBI: Aquastat
29
security for circuit 2 (WP2)
30(N)
Electrical Heater DHW Output
31(L)
32(C) Common line
33(L) 3-way valve for DHW tank
34(N) N common
Output 1 (3-way valve for
35(L)
swimming pool) (*)
Output 2 (Water pump 3 (WP3))
36(L)
(*)
37
Output 3 (Auxiliary boiler or
electric heater) (*)
38
39
Output 4 (Solar) (*)
40
?
N O T E
(*): Inputs and outputs explained in the table are the factory-set options. By means of the unit controller, some other inputs and outputs
functions can be configured and used. Please, refer to the Service Manual for detailed information.
116 TCGB0123 rev.2 - 10/2019
YUTAKI M: Power supply for ATW-RTU and central device
YUTAKI S / S COMBI: Terminals intended for the connection of the Aquastat security
accessory (ATW-AQT-01) for controlling water temperature of the circuit 2.
If DHW tank contains an electric heater, the air to water heat pump can activate it if the
heat pump cannot achieve the required DHW temperature by itself.
Common terminal for the 3-way valve for DHW tank.
The air to water heat pump can be used to heat DHW. This output will be on when DHW is
activated.
Neutral terminal common for 3-way valve of DHW tank and outputs 1 and 2.
The air to water heat pump can be use to heat swimming pool. This output will be ON
when swimming pool is activated.
When there is a hydraulic separator or buffer tank, additional water pump (WP3) is
needed.
The boiler can be used to alternate with the heat pump when the heat pump cannot
achieve the required temperature by itself.
A water electric heater (as accessory) can be used to provide the additional heating
required on the coldest days of the year.
Output for solar combination with Domestic Hot Water Tank.
Description