Hi Tim, Hope you don't mind I have a few queries. a. Can provide a quote for System 3 Inverter ? I am already staying in my flat, so installation will be very messy for me and will hope to complete in as short time as possible. b. How to calculate the BTU required ? I see some specs say FCU is 9k BTU but the compressor only 24k ? I thought 9k x 3 = 27k BTU. Nick