MTA NGSi 07 - Defrost Cycle; Compressor Crankcase Heater; Functions Which Can be Enabled with Hi-T Accessory; Screed Function

TECHNICAL MANUAL
Chapter 9 - User - Control Interface
NGSi 05÷15
31
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
9.21 Defrost cycle
The defrost cycle is a function that works only in heat pump mode and is used to prevent the formation of ice on the surface of the air/air
battery. The formation of ice on the evaporator, which occurs more frequently for very low temperatures of the external environment, in
addition to greatly reducing the thermodynamic efficiency of the machine, leads to the risk of damaging the machine itself.
9.22 Compressor crankcase heater
The crankcase heater is activated when the compressor is off for at least 30 minutes and if the discharge temperature is below a certain
threshold (20°C with a hysteresis of 2.0°C). The crankcase heater is disabled when the compressor restarts.
9.23 Functions which can be enabled with Hi-T accessory
9.23.1 Screed function
A function is implemented in the machines for connecting the screed in radiator systems installation. This function can be activated only if
the Hi-T accessory is installed, therefore for more information, refer to the manual of this control.
9.23.2 Disinfection (Legionella prevention)
The legionella prevention disinfection function is implemented in the machines. This function is enabled only if the Hi-T accessory is
installed, therefore for more details refer to the manual of this control. The parameters related to disinfection are:
• r25: Disinfection setpoint (anti-legionella) (in °C);
• r26: Disinfection duration (in minutes);
• r27: Heat pump in disinfection mode operation setpoint (in °C).
9.24 Handbook for installation configurations
In case of need for clarification on the possible configurations, a “Handbook”has been prepared, which is a technical book consisting of a
collection of system diagrams which highlights some of the proposed installation configurations of our high efficiency heat pumps. The
“Handbook” also sets the task of showing the symbiosis potential with some of our items in the catalogue.
Ask the Head Office in order to consult the technical handbook.
9.25 Tables of settings which can be made by the user and installer
Parameter Description Unit Default Range Visibility Permitted settings Notes
Coo First cooling
setpoint
°C 7.0 5.0÷Co2 U
Hea First heating
setpoint
°C 45.0 He2÷55.0 U
San Domestic hot water
setpoint
°C 48.0 25.0...55.0 U
Co2 Second cooling
setpoint
°C 18.0 Coo÷23.0 U
He2 Second heating
setpoint
°C 35.0 25.0÷Hea U