David from GTZ Air is top notch, he came at the agreed time and diagnosed the AC problem right away, he came prepared with all the equipment needed to find the leak in the system, it was the coil, he checked for warranty on the part and fortunately it was still under warranty, took the part to get it exchanged and got my system up and running again in the same day, he is very knowledgeable and courteous and he is bilingual, the cost of the repair was VERY reasonable! I would definetly recomend him to friends and family when they need a REAL A/C expert that doesn't cost an arm and a leg. Well done David! May your business prosper!