Ammonia-based air conditioning systems, also known as ammonia refrigeration systems, are indeed used in various industrial and commercial applications. However, they are not as commonly used in residential or small-scale air conditioning systems for several reasons:
Toxicity: Ammonia is a toxic gas with a strong and pungent odor. It can be harmful when inhaled, ingested, or when it comes into contact with the skin or eyes. This makes it potentially dangerous for home use, particularly if there is a leak or mishandling of the system. The risk associated with ammonia's toxicity limits its widespread use in residential applications.
Safety concerns: Ammonia is flammable when mixed with certain substances, and it can form explosive mixtures. This adds another layer of safety considerations for handling, storage, and maintenance. Strict safety protocols and specialized equipment are required to mitigate these risks, which may make it less practical for residential air conditioning.
Cost and complexity: Ammonia-based refrigeration systems are more complex and require specialized equipment compared to conventional refrigerants used in residential air conditioning, such as hydrofluorocarbons (HFCs). The installation and maintenance of ammonia systems require highly trained technicians with specific expertise in handling ammonia.
Efficiency and performance trade-offs: While ammonia has excellent thermodynamic properties and can provide efficient cooling, it may not be as effective in smaller-scale air conditioning applications. The design and engineering considerations for ammonia systems may not optimize performance for residential cooling needs, leading to potential drawbacks in terms of efficiency, size, and cost-effectiveness.
Environmental considerations: While ammonia itself is a natural refrigerant with zero ozone depletion potential (ODP) and low global warming potential (GWP), its production and use can still have environmental impacts. The safe containment and proper management of ammonia systems are crucial to prevent potential releases that could harm the environment.
Overall, the use of ammonia in air conditioning systems is more prevalent in large-scale and industrial applications where the benefits outweigh the challenges. For smaller-scale and residential cooling, other refrigerants with lower toxicity, flammability, and easier handling are typically preferred.