A 7.5 ton gas package unit is a type of air conditioning system that is designed to provide cooling and heating for residential and commercial buildings. It is typically used in large buildings, such as office buildings, schools, and hospitals. The unit is a combination of a furnace and an air conditioner, with the furnace providing the heat and the air conditioner providing the cooling. The unit is powered by natural gas, and is usually installed on the roof of the building. The unit is designed to provide efficient cooling and heating, and is often used in areas where there is a need for large amounts of cooling or heating. The unit is also cost-effective, as it is able to provide a large amount of cooling or heating for a relatively low cost.