It's time for service when you see orange flames like this. This is an indication of incomplete combustion that creates dangerous Carbon Monoxide. This unit had flame roll when the burner fired up to the extent the flame shield and front of unit had a build-up of soot. During your maintenance check for an orange color flame or build up of soot or discoloration on the flame guard or above the burner chamber on the exterior of the water heater. If you do, then its time to have the unit evaluated and serviced by a licensed contractor to ensure proper and safe operation. Note typical life of a water heater is 8 - 12 years. If your water heated is approaching this age or older it is recommended you budget for replacement. They can and will fail without warning and can result in a costly clean up. Visit my Home Inspection site for more information and types of services available. You can also see more home inspection defects like this or visit my Home Defect Page to see if your home has any of these defects.