Performed single system cooling maintenance. Checked amps, capacitor, filter, drains, electrical, refrigerant, and cleanliness. The system appears to be cooling fine, but it may be having a TXV issue. I discussed the possible issue with the customer but it seems to be cooling fine as of right now. We discussed the rust in the emergency drain pan and oxidation of the evaporator coil. The customer approved replacement of the emergency pan and performing a no rinse cleaning on the evaporator coil.