Each person engaged in the business of selling or installing air-conditioning plants or equipment which use or require the use of water connections shall pay, in the county in which is located his principal office, an annual state privilege tax of $100 and a county privilege tax of $50; provided, that in each other county in which such person engages in the business of selling or installing such air-conditioning plants or equipment, he shall pay a state license tax of $10 and a county license tax of $5; provided further, that no person subject to the provisions of this section shall be required to pay the license tax levied hereunder in any county other than where he maintains a regular and established place of business for the purpose of selling or installing such air-conditioning plants or equipment.

Any person other than those persons licensed under paragraph one hereof engaged in the business of selling or installing air-conditioning plants or equipment which do not use or require the use of water connections shall pay an annual state privilege license tax for each place of business as follows: In cities of 100,000 inhabitants or more, $30; in cities of 50,000 and less than 100,000 inhabitants, $20; in cities of 10,000 and less than 50,000 inhabitants, $10; in places of less than 10,000 inhabitants, whether incorporated or not, $5.

As used in this section the term "air-conditioning" means the artificial lowering or raising of temperature or the supplying of fresh air by artificial methods.

Upon the payment of the license prescribed by Section 40-12-84, a contractor who installs air-conditioning plants or equipment shall not be required to pay the license prescribed by this section, nor shall any person who has paid the license prescribed by this section, who accepts contracts only for the installation of air-conditioning plants and equipment and no other type of construction work be required to pay the license prescribed by Section 40-12-84.