I was called to a home to perform maintenance on a Rheem water heater. I arrived at the house and began by inspecting the unit to determine the issue. I found that the pilot light was not lit, so I relit it and checked the gas pressure. I also checked the thermostat and adjusted it as needed. After completing these tasks, I tested the water heater to ensure it was working properly. I then cleaned the unit and replaced the filter. Finally, I provided the customer with instructions on how to use the water heater and answered any questions they had.