TECHNICAL MANUAL
Chapter 9
- User - Control Interface
NGSi 05÷15
21
ENGLISH
EN
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
When the system switches from user water to domestic hot water, the working probe changes its function from “water outlet probe” to
“domestic hot water probe”. When the system switches from winter to domestic hot water operation, the compressor does not switch off and is
turned up to the maximum frequency set by the controller, while if it switches from summer to domestic hot water, the compressor is switched
off and waits for the safety pause time.
9.12.1
Probe storage in heating mode
When the system switches from user water to domestic hot water, the working probe changes its function from “water outlet probe” to
“domestic hot water probe”. For this reason, in hot mode, before entering into domestic hot water mode, the last value read by the probe is
stored.
After the domestic hot water temperature control is met, the reference temperature on the system side returns to the temperature previously
stored. The storage function stops:
•
in the moment in which the temperature read by the probe becomes lower than the stored value;
•
or after the expiry of a time equal to
b06
seconds (default 45 seconds).
9.12.2
Domestic hot water production call from digital input
Alternatively to the temperature probe use, the activation of the domestic hot water function can be performed by closing a digital input of
the unit (SAN SAN terminals enabled as digital input). This function is recommended in case of use of two or more minichillers hydronically
connected in cascade to a same storage tank for domestic hot water; in this way the domestic hot water tank function is imposed by the tank
probe connected to the first machine, while the other machines are enabled automatically by digital consent. Only in machines with
domestic
hot water call from digital input
, in addition to enabling the domestic hot water function with
H10=1
, it is also necessary to enable the
digital input setting
H20=0, H45=28
,
H54=128
. For each minichiller (except the last of the cascade), it is necessary to use a relay (not
supplied), controlled by the output 230VAC NO1 and N present in the terminal board, which enables, through its COM and NO clean
contacts, the SAN SAN digital input of the chiller in the next cascade. For this configuration, refer to the wiring diagram below.
Summary of Contents for NGSi 05
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