YHAU-CG/CA Double Effect Direct Fired Chiller/Heaters

120-1,600 TR (422-5,626 kW)

Driven by direct firing of natural gas or light oil, these units provide chilled water and hot water for cooling and heating applications.

  • Innovative, two-step evaporator and absorber design combined with parallel flow cycle.
  • Suited for natural gas or light oil energy sources
  • Variable-frequency drive (VFD) solution pump
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Innovative Design for Superior Efficiency

The YORK® YHAU-CG/CA Double-effect, Direct-fired Absorption Chiller offers a broad range of capacities from 120 to 1,600 TR. This unit uses an innovative, two-step evaporator and absorber along with a parallel flow, which enables lower concentrations and minimizes the potential for corrosion and improves efficiency. Our world-class engineering and service organization helps to simplify the chiller operation over the life of the system.
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Our YHAU-CG/CA Double-effect, Direct-fired Chiller uses an innovative, two-step evaporator and absorber design that enhances efficiency.


Driven by natural gas or light oil energy sources, this unit is suited for a variety of comfort or industrial process cooling applications.


World-class engineering and service teams reduce the cost of ownership by simplifying the operating cycle and deliver worry-free peace of mind.


  • Two-step evaporator and absorber design enhances absorption of the refrigerant into the concentrated solution, reducing overall pressure
  • Variable-frequency drive (VFD) solution pump provides superior part-load performance to reduce gas/oil consumption versus constant speed pumps
  • Control center with graphical, animated, LCD display offers present and past operational status, data recording and chiller safeties accessible at a touch
  • Parallel flow cycle enables lower lithium bromide solution concentrations, reducing crystallization risk and the potential for corrosion
  • High-temperature generator uses stainless steel tubes to maximize reliability by eliminating stress damage
  • Isolation valves on the suction and discharge of the solution and refrigerant pumps allow quick and easy servicing of pumps, which typically have a 60,000-hour life

Two-step Evaporator and Absorber

YORK® YHAU-CG/CA Double-effect, Direct-fired Chillers are uniquely designed with a two-step evaporator that has two pressure levels to divide the absorption process. The chilled water flows in tubes through the two evaporators while a concentrated lithium bromide solution is distilled in the absorber shell-side in the opposite direction. This reduces the solution concentration and overall pressure, making the unit more efficient and reliable than conventional absorption chillers.
See How It Works
Two step graphic showing a YORK Chilled Water System evaporator and absorber.
 Chart showing the parallel flow cycle and two-step design of Absorption Chillers.

Parallel Flow Cycle

The parallel flow cycle divides the solution flow between the low temperature and high-temperature generators into two parallel, balanced paths. Combining our two-step and parallel flow design, the unit can achieve a safer and more efficient operation at a much lower pressure than conventional series-flow designs. Thanks to this innovative design, the LiBr concentration is lower. This results in a relatively low grade for the driving heat source, providing a high coefficient of performance (COP).
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Technical Resources


YHAU-CG/CA Double Effect Direct Fired Chiller/Heaters Sales Guide



Advances in Absorption Technology




Insights From Industry Experts

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