I have purchased a new house from a builder. The house came with a 4 tonne York A/C unit with a variable speed furnace. It simply can't cool the house. Outside temp is 24C, and I can't get the inside below 23C. This is odd, because the 4 tonne is actually oversized from the 3 tonne that the builder recommended. One person I've had a look a the system says it was installed wrong. First, note that the compressor is located about 85 feet from the furnace. I've been told that in this situation, my system should be equipped with (1) a TX valve, instead of a piston (whatever that is), (2) a solenoid valve, (3) a receiver located outside with the compressor, (4) rigid lines, (5) 1 and 1/8 inch gas line, and (6) half inch liquid line. My system has none of these, as far as I can tell anyway. I do note that the lines used are flexible and only measure 7/8 inch (gas) and 3/8 inch (liquid). I don't know what a TX valve, solenoid valve or a receiver is. Can someone help me? What are these things being recommended to me? Do these recommendations make sense. If I proceed, it's going to be costly, so I want to make sure. The builder won't pay for any of it, as it was my idea to relocate the A/C away from the furnace. Any help would be appreciated. Thanks.