I am a professional HVAC contractor, and I recently completed a job at a residential property. The job involved the preventive maintenance of a Viessmann natural gas hot water boiler with an indirect water heater. The boiler was over 10 years old and had not been serviced in several years. During the maintenance, I inspected the boiler for any signs of wear and tear, such as leaks, corrosion, or damage. I also checked the pressure relief valve, temperature and pressure gauges, and the burner assembly. I cleaned the burner assembly and replaced the gasket if necessary. I also inspected the indirect water heater for any signs of wear and tear, such as leaks, corrosion, or damage. I checked the temperature and pressure relief valve, and the anode rod if applicable. I cleaned the anode rod and replaced it if necessary. Finally, I tested the boiler and water heater to ensure they were operating correctly. I checked the temperature and pressure of the water, and the burner assembly was ope