How Absorption Heat Pumps Work

Absorption heat pumps are available in 4 different versions:

  • GAHP-A Type – Gas absorption heater that can produce hot water up to 140°F with high efficiency.
  • GAHP-AR Type – Reversible gas-fired absorption heat pump that alternately produces hot water up to 60°C and chilled water down to 37.4°F, thanks to the inversion of the thermodynamic cycle.
  • GAHP-W LB Type – Gas absorption heat pump designed for geothermal systems.
  • GAHP-W Type – Gas absorption heat pump that simultaneously produces hot water up to 149°F down to 37.4°F.


Heat pumps are systems that transfer heat energy from a lower temperature to a higher temperature (hot source), by inverting the natural thermal flow (in which heat is carried from warm mediums towards cooler ones). This flow capability works whether one wishes to provide heating or cooling with a single piece of equipment.

In heating mode, the system supplies the room heat “pumped” from the outside and the heat energy to fuel the heat pump itself, thereby obtaining high energy efficiency. The natural gas absorption heat pump differs from traditional electrical heat pumps due to the energy that it uses.  Instead of consuming electric energy to operate a vapor compression cycle, the absorption heat pump consumes gas in a premixing burner, which heats a solution of water and ammonia in a completely sealed absorption circuit.

In generic terms, absorption heat pumps are hydronic type systems, as they heat and/or cool the water that is required. One of the many advantages of this characteristic is that it allows the heating and cooling input temperature to be managed better, making for precise adjustments to indoor comfort, thus increasing the operating efficiency of the entire system.

How Engine-Driven Heat Pumps Work


The engine-driven gas heat pump air conditioning systems utilizes an efficient reciprocating engine running on a natural gas to produce the shaft horsepower to turn a scroll vapor compressor using 100% non-ozone destructive refrigerants.  The heat pump cycle uses the compression cycle to turn the liquid refrigerant into a gas.  As it does this, it absorbs hear from its surroundings and conversely when a gas is concentrated and turned into a liquid it generates heat. Using these principles, the compressor, driven by an economical engine circulates the refrigerant thru the gasification and liquefaction cycles.  The cooling and heating is accomplished by this circulation.  As the basic principle of operation is the same, the primary advantage of an engine-driven heat pump is the operating cost.