Performed preventative maintenance for air conditioning for the main house system and master bedroom system. Customer also had a concern with his child’s bedroom not getting air. Upon inspection I found the vents that are visible are false vents. The floor vent that is used for air was covered by an item in the bedroom. Removed the item from over the vent and showed the customer. Inspected all the electrical components. Confirmed proper high and low voltages. Tested the amp draw of the blower, compressor and fan motor. All were operating within the manufacturer specs. Tested the temperature split between the supply and return. System is operating at a 20° For main system and master bedroom system differential on a 77° day. Customer replaced the Merv 11 (16x25x5) air filters for both systems. Systems are operating properly at this time. House has 3 full systems in total.