I just bought a house and are having issues with my A/C. I had a service tech from my home warranty come out and he concluded that the liquid line is kinked where it makes a 90 degree turn to vertical coming out of the condenser. It looks like the tube was straight to begin with and bent on purpose to make the 90 degrees. He says it's the problem which is causing my A/C to shut itself off every 5 minutes or so as the pressure builds. He also said that the brand I have, Goodman, is not a good brand and that I need a condenser pad put underneath the unit. What I want to know is what is a rough estimate cost to replace the liquid line and also what is the condenser pad used for? Do I really need it? The unit is sitting on flat concrete right now. Also, is Goodman really a bad brand or is he just trying to get me to buy a new unit?