Replacement of old smoke and carbon monoxide detectors with company supplied detectors. Detectors have a 5 year warranty with Haas and Sons Electric and a 10 year manufacturer warranty. We were called out today to look at replacing some smoke and carbon monoxide detectors. I noticed the detectors were starting to yellow and a few chirped on their own indicating that they needed to be replaced. While assessing the panel, I noticed that there was one multi wire branch circuit that was not on a two pole breaker as well as that the panel was lacking surge protection. I gave a solution to address the breaker and add surge protection along with the smoke detectors. The customer was only interested in the smoke and carbon monoxide detectors at this time, but would be interested in the surge protector and breaker in the future. We replaced at total of 9 detectors, 3 Smoke/CO units and 6 Smoke units. 2 smoke, 1 combo in the basement; 1 smoke, 1 combo on the first floor; 3 smokes and 1 combo