Hot Water Driven Vapour Chillers

Thermax has the complete range of hot water chillers, specially designed for low temperature, medium temperature and high temperature hot water.
Cogenie is a simple and compact small capacity single effect hot water chiller. It is widely used for combined heat power and cooling (CHPC) based air-conditioning application is USA and Europe.
Low temperature hot water chillers are further classified as Low Capacity (LT Series) and High Capacity (5G Series)
Operating Range
  • Capacities: 35 to 700 kW
  • Chilled water temperature: Up to 3.5ºC
  • Hot Water Temperature: From 75ºC to 120ºC
  • COP: 0.65–0.72


Medium temperature hot water machine is one of the oldest and most established absorption machines, driven by low grade energy and consuming minimum power. It follows the single effect technology, where the gain in concentration of the absorbent is achieved using only one generator.
Operating Range
  • Capacities: 350 to 7650 kW
  • Chilled water temperature: Up to 3.5ºC
  • Hot Water Temperature: From 120ºC to 150ºC
  • COP: 0.7–0.75

    High temperature hot water machines are of the double effect type, where, the gain in concentration is achieved in two steps. The primary generator (referred as High Temperature Generator or HTG) produces vapour, whose latent heat is transferred to lithium bromide in secondary generator (referred as Low Temperature Generator or LTG).

    Thermax double effect absorption chillers are designed based on its proven Advanced Series Flow technology. This ensures that the highest concentration and highest temperature of Lithium Bromide solution doesn’t occur simultaneously. Due to this the rate of corrosion is negligible compared to the para flow or reverse flow technologies.

    Operating Range
    • Capacities: 175 to 8800 kW
    • Chilled water temperature: Up to 1ºC and -2ºC with brine
    • Hot Water Temperature: From 150ºC to 180ºC
    • COP: 1.4 – 1.45


    5G Series comes with two stage evaporation & condensation technology (also known as Twin design). This ensures the lowest specific heat input as compared to other contemporary VAMs, making them the most efficient VAM in its category. This results in lowest operating cost throughout the life cycle of the VAM and lowest water consumption in cooling tower thus saving precious water.
    Operating Range
    • Capacities: From 200 to 1380USRT (700 to 4850kW)
    • Chilled water temperature: Up to 0ºC (34ºF)
    • Hot Water Temperature: From 75C to 120C
    • COP: 0.65–0.72
    • Hot water from solar collectors
    • Process condensate heat recovery
    • Engine jacket water
    • Heat recovery from flue gases

    Hot water fired machines are used for process cooling, industrial and comfort air-conditioning. A popular application of hot water fired machines is Charge Air Cooling of DGs & Gas Turbines. These machines typically find application in cases where the hot water source is already present, as part of an industrial or commercial process.

    Hot water fired chillers are generally used in industries like: Chemicals, Pharmaceuticals, Paper, Textiles, Captive Power Plants, Steel, Hotels & Hospitals, Restaurants, Software Parks, Offices, Educational Institutions, Museums, etc.