i-HWAK V4
Chillers and inverter air / water heat pumps with axial fans
10
5
TECHNICAL CHARACTERISTICS
The i-HWAK V4 water chillers and heat pumps series are designed for applications in residential and commercial areas, These units
are extremely versatile and can operate in heat pump mode with the ability of producing hot water at a temperature of 58°C for
environmental heating and sanitary applications. The INVERTER compressor with brushless DC motor technology, matched with
electronic expansion valve, pump and variable speed blower are generally used for optimizing the power consumption and
efficient operation of the refrigerating components.
5.1
FRAME
All the unist of i-HWAK V4 series are made up of hot-galvanised thick sheet metal, painted with polyurethane powder enamels at
180°C to ensure the best resistance against atmospheric agents. The frame is self-supporting with removable panels. All screws
and rivets for outdoor installations are in galvanized steel.
5.2
REFRIGERANT CIRCUIT
The refrigerant gas used in these units is R410A. The refrigerant circuit has been manufactured by means of international primary
brands components and according to the UNI EN 13134 Rule concerning welding procedures. The refrigerant circuit includes: 4
way reverse cycle valve, electronic expansion valve, liquid separator, liquid receiver, valves for maintenance and control, pressure
safety device, pressure transducers to accurately adjust the evaporating and condensing pressures, filters for throttling valve to
avoid its clogging.
5.3
COMPRESSORS
The installed DC inverter compressors are rotary hermetic twin rotary type designed to be used with R410 refrigerant.
The compressors are mounted in a separate chamber, isolated from the air stream in order to reduce the noise, and are equipped
with crankcase heater, In order to avoid the oil dilution which may cause seizure of the compressor. The crankcase heater
operates when the compressor remains off for at least 30 minutes and if the discharge temperature is below 20°C (with hysteresis
of 2.0°C). When the compressor restarts, the crankcase heater will stop operation. The crankcase heater works even if the unit is
in shut off mode, which will protect the compressor from restartup failure.
We recommend you to turn ON the unit and to put it in standby mode at least for 6 hours before starting the operation, especially
if the system has been completely turned off for a period of time.
The checking of the compressors is possible through removing the frontal and lateral panels of the unit allowing easy maintenance
of the compressors even when the unit is operation.
5.4
AIR SIDE EXCHANGERS
The air side exchangers are made up of copper pipes and aluminium fins. The diameter of the copper pipes is 9.52mm for the
model 09 and 5/16” for the other models 12 and 15, the thickness of the aluminium fins is 0,1mm. The tubes are mechanically
expanded into the aluminium fins to improve the heat exchange factor. The geometry of these condensers guarantee a low air
side pressure drop and, then, the use of low rotation (and low noise emission) fans.
5.5
FANS
The fans are axial type with aluminium aerofoil blades. They are statically and dynamically balanced and supplied complete of the
safety fan guard according to the CEI EN 60335-2-80 Rule (safety for electrical apparatus of domestic and similar use). They are
mounted on the unit frame by interposition of rubber vibration dampers. The electric motors are all brushless DC type with 8
poles (about 200/1000 rpm). The motors are directly driven with an integrated thermal overload protection. The protection class
of the motors is IP X44.
5.6
USER SIDE HEAT EXCHANGERS
The user side heat exchangers are made up of AISI 304 stainless steel braze-welded plates type. The user heat exchangers are
factory insulated with flexible close cell material and can be equipped with antifreeze heater (KA optional). Each heat exchanger is
provided with a temperature sensor working as antifreeze protection that activates the circulator, even in the case when the unit
is turned off when the conditions set in the controller have been occurred.
5.7
ELECTRIC BOX
The electric box is manufactured according to the current European Union laws. The accessibility to the board is possible after
removing the cover panel of the unit using proper tools. The protection degree is IP24. The terminal board is supplied with voltage
free contacts for remote ON-OFF, winter/summer change over, auxiliary heater, sanitary water temperature sensor control of
external 3-way valve and free contacts for remote control panel and for the management of the dual set point of operation.
5.8
CONTROL SYSTEM
All the units of i-HWAK V4 series are standard supplied with a microprocessor adopting an overheating control logic program
through the electronic expansion valve which is driven by the pressure transducers signals. The microprocessor is also capable of
controlling the following functions: water temperature regulation, antifreeze protection, compressors’ time setting, compressor
automatic starting sequence, alarm reset, alarm management and operating LED. Upon request, the microprocessor can be
connected to a BMS remote control system and to the simpler HNS system with our terminal units. The control system together
with the INVERTER technology and the on board sensors continuously monitor and adapt the performance of the inverter
