Any consumer may, upon written application accompanied by a deposit in an amount established by the council, have his meter tested for accuracy by the city. If the meter registers a divergence from accuracy greater than three (3) percent, the deposit shall be refunded to the applicant and the indicated adjustment made in the water service charges for a total period not longer than the then-current period and the monthly period immediately preceding. If a meter so tested registers within three (3) percent of accuracy, the deposit shall be retained by the city as a fee to pay the cost of such test. All inaccurate and defective meters shall be replaced by the city immediately when detected. (1976 Code § 14-6-9)