PROJECT DESCRIPTION

Suitable for cooling and heating musts and wines, controlling fermentation temperatures, tartaric stabilization and air conditioning rooms with the possibility of managing multiple users simultaneously.

• Satin 304 stainless steel

Structure and paneling in stainless steel, the material of excellence to guarantee durability and aesthetic finish over time.

 

• Heat pump

Heat pump cycle inversion system allows heating up to +40°C.

 

• Temperature

Standard programmable temperatures from -10°C to +40°C

 

• Hydronic system

Hydronic system installed inside the refrigerator, with thermally insulated 304 stainless steel open circuit storage tank and water pumping kit managed by one or more multi-impeller 304 stainless steel electric pumps.

 

The KRIOS model is a reversible air-cooled chiller, designed for industrial use and outdoor installation (IP65 protection rating).

The wide range of available options and accessories allows this machine to meet most needs in the industrial field.

 

KRIOS is therefore the solution for all applications that require high performance, reliability and continuity of operation.

 

All models are equipped with a high efficiency finned coil, brazed plate evaporator or stainless steel coil immersed in a hydronic tank.

 

The standard hydraulic storage tank also ensures excellent precision in temperature control even with highly variable thermal loads to the user and simplifies installation.

 

The units are equipped with finned condenser, axial fans and scroll compressors installed on independent refrigeration circuits.

 

The refrigerant used is R410A.

 

Management is entrusted to a thermoregulator control capable of managing all the main functions of temperature regulation in complete autonomy, while alarms and blocks are indicated by indicator lights.

All units use top brand components and are designed and manufactured in compliance with CE regulations.

 

The combination of these solutions allows to improve energy efficiency values, maximizing the seasonal performance indices ESEER (*) and SCOP (**).

 

The units are available in standard version with 400V/3/50Hz power supply except the MINI KRIOS model which is 220V single phase. Other voltages on request.

 

To meet the various system requirements, the liquid coolers are available with open tank or closed circuit hydraulic circuits.

 

The standard product, intended for EEC and EFTA states, is subject to:

 

• Machinery Directive 98/37/EC as amended by 2006/42/EC
• Low Voltage Directive 2014/35/EU LV
• Electromagnetic Compatibility Directive 2014/30/EU EMC
• Pressure Equipment Directive 2014/68/EU PED

All data reported in this catalogue refer to standard machines and nominal operating conditions (unless otherwise specified).

(*) Seasonal energy index ESEER: since there are no specific performance indices available for industrial applications in partial load conditions, the seasonal performance indices ESEER are reported for each machine.

The seasonal performance index ESEER (European Seasonal Energy Efficiency Ratio) used in the European design context, characterizes the weighted average efficiency of a chiller.

This index expresses the relationship between the useful effect (total energy removed) and the energy expenditure (electrical energy consumed) of a refrigeration machine during the entire operating season.

In relation to the different operating conditions, and the frequency with which they are reached, these indicators are calculated by assigning a different energy weight to the corresponding performance of the unit. For example, ESEER = 4 means that, during an entire operating season, for every 4 thermal kWh subtracted, an average of 1 kWh of electrical energy will be spent.

 

—

 

(**) Seasonal efficiency coefficient SCOP – EN 14825

The Energy-related-Products Directive – Erp (Eco-design) is a framework directive that through specific implementing regulations regulates the eco-sustainable design requirements for all products that use energy, including heat pumps up to 400 kW.

The seasonal efficiency index SCOP, defined by the EN14825 regulation, allows the comparison of energy performance between different heat pumps applied to the same building.

It is calculated as the ratio between the total energy required by a building during the heating period and the electrical energy consumed during the entire winter period, taking into account that, in addition to the heat pump, the system may include other auxiliary devices such as:

 

• Auxiliary heating systems; – electrical panel;
• Crankcase resistors.

 

Advantages of using the inertial tank

 

In a system dedicated to an industrial process, the thermal load of the user can undergo large and sudden variations, or remain for long periods close to conditions very distant from the nominal ones.

As a result, the chiller that powers this system sometimes operates at maximum capacity and close to its operating limits, and sometimes with frequent ON and OFF cycles.

Such cycles always prove to be harmful to the life of the compressors and often insufficient to avoid significant fluctuations in the water temperature, which is also absolutely inconvenient from both an energy and process point of view.

The advantages resulting from the use of the buffer tank installed in all KRIOS units as standard can be summarised as follows:

• Availability of a water reserve at a specific temperature for the process to be controlled: in this way the “energy stored” in the tank can compensate for imbalances due to variations in user load.
• Operation of compressors in particularly stable conditions: in this way the refrigeration unit can work at a practically constant inlet temperature. Together with the constancy of the water flow, this is one of the essential conditions to guarantee maximum compressor life.
• Reduction of the frequency of starts and guarantee of a sufficient duration of each compressor running period and each compressor idle period.

 

Testing

 

All coolers are tested to ensure proper operation.

In particular, the following are checked:

 

• Correct assembly of all components and absence of refrigerant leaks;
• Electrical safety tests as prescribed by EN60204-1;
• The correct functioning and control of all operating parameters;
• Temperature probes and pressure transducers;

 

During installation, the machines therefore require only electrical and hydraulic connections, ensuring a high level of reliability.

 

Compressor

 

Orbiting spiral scroll compressors with 2-pole electric motor, mounted on rubber anti-vibration mounts and complete with protections against overtemperatures, overcurrents and excessively high exhaust gas temperature values.

A crankcase heater, automatically powered when the unit stops (provided the chiller is kept powered), prevents the oil from being diluted by the refrigerant when the compressor stops, thus ensuring correct lubrication of the mechanical parts even at low ambient temperatures.

Thanks to the limited mass of the rotating components and the absence of suction and delivery valves, scroll compressors have numerous advantages: greater energy efficiency, reduced pressure drops in suction, significant reduction in noise levels, reduced vibrations on the delivery, great resistance to liquid shock.

For some models, the compressors are installed inside a compartment separate from the condensing compartment, allowing maintenance activities even with the machine in operation.

The models use two compressors connected in parallel or independently for each circuit, which allows for increased efficiency at partial loads, maximising the ESEER seasonal performance index (*).

This solution, through the “unloading” function, also allows the system to be started up and the machine to operate even under conditions that are very different from the nominal ones.

 

Evaporator

 

High efficiency brazed plate exchanger, or 304 stainless steel spiral coil.

Installed inside the inertial storage tank, the evaporator with a high exchange surface cools the process fluid that flows in contact with the surface, exchanging heat with the refrigerant fluid that evaporates inside it.

This particular technical solution allows to operate with high flow rates and low operating pressure drops, guaranteeing a high level of reliability in particularly demanding industrial applications and also with liquids containing impurities.

All evaporators used in refrigerators can also handle antifreeze solutions and, in general, other liquids that are compatible with the materials making up the hydraulic circuit (see materials in contact with the process fluid).

 

Condensing/evaporating coil

 

Finned pack exchanger, made up of copper tubes and collectors, corrugated aluminum fins, and galvanized sheet metal shoulders. They have been designed and drawn to achieve high EER efficiency values both in condenser and evaporator function.

The condensing batteries are equipped with a distributor for a correct supply of the refrigerant circuits during heat pump operation. The collection of condensation water for some models, occurs by means of a drip tray, which covers the entire base of each battery and which is equipped with drain connections.

 

Electric fans

 

Axial suction fans, with die-cast aluminium or die-cast plastic body, sickle-shaped blades made of aluminium.

Equipped with built-in thermal protection.

All fans are statically and dynamically balanced, equipped with an external safety protection grille.

The motors used are 4 or 6 pole and of the external rotor type and are protected with a chain of thermistors.

The standard regulation is ON/OFF managed by a pressure transducer. High efficiency inverter fans are available as an option. The inverter electronic switching technology, thanks to a continuous and efficient regulation of the fan speed at partial loads, allows the reduction of consumption together with the decrease of noise levels.

Refrigeration circuit

 

The refrigeration circuit includes:

• Double mechanical thermostatic expansion valve with external equalization: located at the evaporator inlet (one for cold operation and one for hot operation), they regulate the gas flow according to the thermal load. This valve optimizes the compressor operation by ensuring a sufficient degree of superheating of the suction gas in all operating conditions.
• 4-way cycle reversal valve: reverses the refrigerant flow when changing summer/winter operation and during defrost cycles in heat pumps.
• Hygroscopic molecular sieve dehydrator filter: allows impurities and any traces of humidity present in the refrigeration circuit to be retained.
• Liquid refrigerant flow and humidity indicator: Placed on the liquid line, it allows you to check the correct refrigerant gas charge (presence of bubbles) and the possible presence of humidity in the refrigeration circuit.
• High and low refrigerant pressure gauges.
• High HP and low LP refrigerant pressure switches.
• High pressure transducer: for defrosting management and for step or electronic regulation of the fans (when present).

 

All the brazing for connecting the various components is done with silver alloy and the cold pipes are coated with heat-insulating material to avoid the formation of condensation.

 

Structure and panelling

 

Structure and panelling in satin-finish 304 stainless steel, radiator protection nets in flexible plastic or electro-welded stainless steel net.

 

Hydronic group

 

INERTIAL STORAGE TANK

All models are equipped with an open vessel storage tank (containing the evaporator) externally isolated by an insulating and anti-condensation layer. Sized to work in closed hydraulic circuits. The materials used are 304 stainless steel.

HYDRAULIC BY-PASS

All units with plate exchangers are equipped with an internal by-pass between the water flow and return or equipped with a dedicated pump. In the event of an incorrect interception of the inlet and outlet connections, the by-pass allows the integrity of the machine and the pump to be preserved, allowing the passage of a minimum flow rate of fluid necessary both for the intervention of the antifreeze alarm and for the protection of the pump.

Warning: the by-pass has the sole purpose of preserving the integrity of the machine in the event of an incorrect closing of the shut-off valves. Operation in by-pass with continuous cycles and prolonged periods of time is strongly discouraged.

CIRCULATION PUMPS: The pumps are centrifugal type with stainless steel impellers with IE2/IE3 class motors depending on the model (international standard IEC 60034-30) with thermally insulated silicon carbide/silicon carbide/EPDM seals.

 

Electrical panel

 

The electrical panel is made and wired in accordance with the Low Voltage Directive, on electromagnetic compatibility.

It consists of an electrical box made of polycarbonate or stainless steel, which houses the components fixed on a bottom panel, and a door that opens on hinges and closes on a sealing gasket fixed on the electrical box itself, protected by a transparent opening door in polycarbonate and the main switch equipped with a safety door lock (the door cannot be opened without first having removed the voltage from the electrical panel). The electrical panel made with primary brand components guarantees the protection against atmospheric agents necessary for installing the refrigerator outdoors (IP65 protection rating). The power section includes automatic magnetothermal switches for the protection of power devices such as compressors, fans and centrifugal pumps, a series of contactors and a phase monitor for the protection of the machine from phase failure and incorrect phase sequence. The control section includes the transformer for powering the auxiliaries.

 

Safety and control devices

 

High pressure transducers: Detecting the compressor delivery pressure and are used by the electronic control for the following functions: high pressure measurement and alarm, high pressure unloading, condensation pressure control via electronic or STEP regulation of the fans.

Temperature probes: positioned on the hydraulic circuit, they detect: water temperature from the storage tank.

Automatically reset high and low pressure switches: these are located on the high and low pressure sides of the refrigeration circuit respectively and stop the compressor in the event of abnormal operating pressures.

 

Standard thermostat control

 

Control and management are entrusted to a thermoregulator with parameters displayed on the screen.

The ease of use of this thermostat allows any user to view and modify the main operating parameters of the system.

 

WARNING LIGHTS FOR MALFUNCTION ALARMS

 

• high condensation pressure alarm;
• low evaporation pressure alarm;
• antifreeze alarm on the water leaving the evaporator;
• thermal protection alarm

 

Also available in versions without exchanger and with double compressor.