1. Oxidation is a sensitive atmospheric equilibrium that is disrupted by too much HC and NOX. This affects the photosynthesis and respiration of plants, limiting their growth.

2. Acidification, diesel engines mainly emit NOX, which can form nitric acid with water. In addition, SO2 and water can generate sulfuric acid. Both of these are strong acids that can affect the leaves of plants and attack their roots, thereby reducing their ability to absorb water and inorganic salts.

3. Photochemical smog is formed in densely populated areas when large amounts of HC and NOX are exposed to sunlight. Smoke contains a lot of pollutants, presenting a brown color of NO2. The nitrogen oxides and hydrocarbons in smoke can affect the respiratory system, increase susceptibility to infection, and particularly lead to respiratory disorders.

4. Particles in the air are the consequence of exhaust gases emitted by diesel engines. Particles are small carbon nuclei (<10um) on which hydrocarbons can deposit and concentrate, bringing hydrocarbons with mutagenicity and pathogenicity into the lungs.

1. Poor refrigeration efficiency leads to high temperature inside the unit and shutdown;

2. If the water tank leaks and the water level inside the storage tank decreases, the unit will not be able to operate normally.