Jake K. I arrived for a friends and family fall tune up. I first spoke with the homeowner and found the system to be running well. She showed me the thermostat and I found the system set to emergency heat on this 58 deg day. We discussed how the system runs in heat pump mode and when it’s best to switch it to emergency heat vs heat pump modes. She should me the location on the indoor unit and I inspected the downflow air handler. I did find the blower wheel to be a little dirty but still running well. I did find the evaporator coil to be mostly clean but the fins on the coil are starting to corrode. This can make it difficult to clean the coil if it were to be done. By trying to clean the evaporator coil it could cause more damage to the evaporator than what it might be worth trying to get it clean vs how dirty it is and how much damage might possibly be done to the coil. The system in the shape it is in now is running well and all electrical components are within all manufacturers ran