Arrived at unit to do a maintenance on Samsung double head condenser unit. I took off top of unit and hoses out inside and out of any debris in condenser. I took off condenser cabinet and motherboard (good), refrigerant (good), both fan motors (good), tightened electrical. After I went up to attic to service both new systems installed a year ago. I changed both filters at each unit. Both were 16*25*5 air filter. I checked blower motors (good), motherboards (good), no single secondary motor controls on either unit, both have ecm. Lastly I went to check out bottom floor air handler. Checked out motherboard (good), blower motor (good). Changed out air filter at unit. Size was 29*25*5, for next visit, so we’ll have all correct sizes. Charging today for three air filters and a surge protection opiate condenser.