I was called to a home to perform a preventive maintenance check on a Burnham K2 natural gas hot water boiler. The boiler was over 10 years old and had not been serviced in a while. I inspected the boiler and found that the burner was not working properly. I replaced the burner and tested the boiler to ensure it was working properly. I also checked the pressure relief valve and the temperature and pressure relief settings. I also checked the electrical connections and the gas supply line. I also cleaned the boiler. The homeowner was very happy with the work and thanked me for my service.