Air-cooled chillers for outdoor installation

With Free-Cooling function

Whenever cooling is required, even at low outdoor temperatures, year-round chillers with free-cooling capability are the right choice.

In relation to standard chillers, the Free Cooling units are equipped with an additional air-cooled heat exchanger. If the ambient temperature drops below the water inlet temperature into the unit, the free cooling function will be activated.

Water from the plant flows through the additional heat exchanger by switching over the internal number of water circuits. The water is coolved via the outdoor air, which reduces the compressor runtimes. If the ambient temperatures is low enough (round about 2 °C) the compressors are not used at all any more.

The whole cooling capacity can be achieved by the free cooling heat exchanger. The entire electrical power consumption of the compressors can be saved. Only the fans are in operation to cool down the water. The free cooling function allows you to ensure excellent energy efficiency throughout the whole year.

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    GLFC 0152-0612 BD2 (37 – 162 kW)

    Only for cooling during production processes!


    Refrigeration circuit:
    • Cooling capacity from 40 up to 377 kW
    • 2 Copeland scroll compressors per refrigerant circuit
    • 1 or 2 refrigeration circuits
    • 1 plate heat exchanger as evaporator
    • GLHM as stand-alone module available (GLHM #### -00)

    Models:
    • Standard version: optimized price in 18 capacity sizes
    • SL version: super low noise; with reduced sound power from 9 up to 11 dB(A) in 18 capacity sizes

    Equipment:

    • Unit with free cooling function for high energy-saving potential
    • The free cooling mode is activated starting from 1 °C temperature difference between outdoor air and medium inlet temperature.
    • 3-way valve for the optimization of the water paths and the efficiency
    • Operation down to -30 °C outdoor temperature possible as option
    • Parallel compressor and free cooling operation possible
    • One refrigeration circuit
    • Two scroll compressors each per refrigerant circuit for best possible redundancy
    • Autoadaptive microprocessor control
    • Controller type: HVAC Systems Step II
    • Unit main switch
    • Automatic circuit breakers for all electric consumers
    • Master/slave operation with GEA HVAC System unit series available as an accessory item
    • Connection to BMS via optional interface

    Can be delivered in two different versions:
    • GLFC 0152 – 0612 BD2 as standard unit
    • GLFC 0152 ... 0612 BD2.SL in especially quiet version

    • Outdoor installation
    • Scroll compressor
    • Cooling
    • Standard motor with axial fan and Ex protection (ATEX)
    • Refrigerant R-410A
    • Plate heat exchanger
    • Master/slave operation is possible
    • BMS integration is possible
    • Unit as low-noise model
    • Unit with free cooling
  •  

    GLFC 0604-1204 BD2 (153 – 326 kW)

    Only for cooling during production processes!


    Refrigeration circuit:
    • Cooling capacity from 40 up to 377 kW
    • 2 Copeland scroll compressors per refrigerant circuit
    • 1 or 2 refrigeration circuits
    • 1 plate heat exchanger as evaporator
    • GLHM as stand-alone module available (GLHM #### -00)

    Models:

    • Standard version: optimized price in 18 capacity sizes
    • SL version: super low noise; with reduced sound power from 9 up to 11 dB(A) in 18 capacity sizes

    Equipment:
    • Unit with free cooling function for high energy-saving potential
    • The free cooling mode is activated starting from 1 °C temperature difference between outdoor air and medium inlet temperature.
    • 3-way valve for the optimization of the water paths and the efficiency
    • Operation down to -30 °C outdoor temperature possible as option
    • Parallel compressor and free cooling operation possible
    • One refrigeration circuit
    • Two scroll compressors each per refrigerant circuit for best possible redundancy
    • Autoadaptive microprocessor control
    • Controller type: HVAC Systems Step II
    • Unit main switch
    • Automatic circuit breakers for all electric consumers
    • Master/slave operation with GEA HVAC System unit series available as an accessory item
    • Connection to BMS via optional interface

    Can be delivered in two different versions:
    GLFC 0604 – 1204 BD2 as standard unit
    GLFC 0604 -1204 BD2.SL in especially quiet version

    • Outdoor installation
    • Scroll compressor
    • Cooling
    • Standard motor with axial fan and Ex protection (ATEX)
    • Refrigerant R-410A
    • Plate heat exchanger
    • Master/slave operation is possible
    • BMS integration is possible
    • Unit as low-noise model
    • Unit with free cooling
  •  

    GLFC 2150-2600 DA2 (286 – 1212 kW)

    Only for cooling during production processes!

    Refrigeration circuit:

    • Cooling capacity from 286 up to 1212 kW
    • 1 compact screw compressor per each refrigeration circuit
    • 2 refrigerant circuits
    • 1 Shell & tube heat exchanger as evaporator
    • GLHM as stand-alone module available (GLHM #### -00)

    Models:
    • Standard version: optimized price in 17 capacity sizes
    • SL version: super low noise; with reduced sound power from 9 up to 11 dB(A) in 16 capacity sizes

    Equipment

    • Unit with free cooling function for high energy-saving potential
    • The free cooling mode is activated starting from 2 °C temperature difference between outdoor air and medium inlet temperature.
    • Three 2-way valves for optimizing water circuits and efficiency
    • Operation down to -25 °C outdoor temperature possible as option
    • Operation with medium outlet temperatures down to 20 °C possible
    • Parallel compressor and free cooling operation possible
    • Two refrigerant circuits
    • One screw compressor per refrigerant circuit for best possible redundancy
    • Screw compressor with continuously variable capacity control
    for constant water outlet temperature
    • Additional sub-cooler circulation for optimized energy efficiency in chilled water operation
    • Autoadaptive microprocessor control
    • Controller: HVAC systems Step III
    • Unit main switch
    • Automatic circuit breakers for all electric consumers
    • Master/slave operation with GEA HVAC System unit series available as an accessory item
    • Connection to BMS via optional interface

    Can be delivered in two different versions:
    • GLFC 2150 - 2600 DA2 as standard unit
    • GLFC 2150 - 2540 DA2.SL as especially quiet version

    • Outdoor installation
    • Screw compressor
    • Cooling
    • Standard motor with axial fan and Ex protection (ATEX)
    • Refrigerant R-134a
    • Shell and tube heat exchanger
    • Master/slave operation is possible
    • BMS integration is possible
    • Unit as low-noise model
    • Unit with free cooling

Method of operation of an air-cooled chiller with free cooling function:

Summer operation:

Sommerbetrieb

In summer operation the unit functions as a traditional air-cooled chiller. The free cooling function is not active.

Transitional mode:

Übergangsbetieb

 
As soon as the outside air temperature falls slightly below the water inlet temperature of the unit, the unit's internal water circuits are switched over and the additional free-cooling heat exchanger becomes active.

The missing cooling capacity is provided by the part-load mode of the compressor.
Already during transition seasons significant energy savings can be achieved by working in parallel mode.

Winter operation:

Winterbetrieb

At sufficiently low outdoor temperatures, the entire compressor mode is not necessary.
All the required cooling capacity can be provided via the free-cooling heat exchanger.

If the outdoor temperatures continue to drop, the air flow rate is reduced in order to ensure constant medium outlet temperatures and to further lower the energy consumption.

Contact Us

DencoHappel GmbH

Südstraße 48
44625 Herne
Germany
+49 2325 468-00
+49 2325 468-222
Areas of Application

Free-cooling units make sense where there is a cooling demand if the ambient temperatures are low over several hours during the year.

Such as for instance:

  • Telephone data centers
  • Production facilities
  • Data centers
  • Buildings with glass facades
  • Buildings with high internal loads
  • Hospitals
DH-Points
  • Energy saving potential of up to 50%
  • Reduced CO2 emissions
  • Short pay back times
  • From 1 K temperature difference between ambient and water inlet temperature, the free-cooling operation starts to work
  • Precise leaving water temperature control at low ambient temperatures through a modulating 3-way- valve.
  • Reduced operating hours of the compressor
  • Reduced maintenance and service costs
GLFC Freecooling, 37-302 kW
With freecooling function for high energy-saving potential and 2 or 4 scroll compressors for applications in telephone exchanges, IT facilities and places of production

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