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TECHNICAL MANUAL

Chapter 21

- Double setpoint kit (optional accessory)

NGSi 05÷15

ENGLISH

The data in this manual are not binding and they can be modified by the manufacturer without notice.

Reproduction of this manual is strictly prohibited

2 1 . 4

M i n i c h i l l e r s e t t i n g s

Double setpoint mode setting parameter H82 (from maintenance menu):

Inputs/outputs setting:

•

H44=26

for the digital input DI7 setting (SE-SE terminals)

•

H62=25

for the digital output DI7 setting OC2 (NC2,N2,NO2 terminals)

2 1 . 5

I n s t a l l a t i o n n o t e s

Humidity switch

The humidity switch relay must be connected as NC.
There are two possible options:

1. dehumidification not necessary (double setpoint activation):

when the relay is not activated, water is sent to the floor system (second setpoint)

2. dehumidification necessary (double setpoint deactivation):

when the relay is activated, water is sent to the fancoils (second setpoint)

Relay

The three-way valve can be connected directly to the relay with switching contact on the unit (5A resistive, 1A inductive, 230 VAC),
connecting it to terminals NC2, N2 and NO2 (if a valve with 3-point power supply is available), or to terminals N2-NC2 (if the valve
available has 2-point power supply, with return spring).
However, an external relay, including in the double setpoint kit, should be used to allow connection with higher loads (up to 8A resistive,
1,6A inductive) and at the same time to separate the power supply lines of the minichiller, three-way valve and fancoil (in this case, suitable
electrical protection must be provided for the fancoil power supply line).
In this second case, the relay must be installed on DIN bar of the user terminal board on the unit, connecting the power supply to terminals
N2-NC2. The three-way valve must then be connected to the NO COM NC relay outputs if it has 3-point power supply, or to NO-COM with
2-point power supply with return spring.
For setting these parameters, refer to the tables in Point 9.25, while for the electrical connections refer to the electrical diagrams in Point
21.8.

Three-way valve with 2 or 3 point power supply (not included in kit)

The three-way valve is used to divert the flow between the floor system and the fancoils.
For three-way valves with 2 point power supply (return spring), the default line must be connected to the floor system.
For three-way valves with 3 point power supply, the valve line with the water connection to the floor system must receive power as shown in
the wiring diagrams provided in Point 21.8. In these diagrams, the floor side or system side is the line to which the valve must switch when
it receives power.

2 1 . 6

S e t t a b l e s e t p o i n t s

Use the SET key to set the setpoints from the panel on the unit.

H82

OPERATION

Pop-up selection menu appears on CRH

Standard mode

Double setpoint active in summer

Double setpoint active in winter

Double setpoint active in summer and winter

Setpoint type

Setpoint (summer/winter)