In my oppinion, carrier and lennox are top of the line.  They also have lower line equipment.  If you are looking for the best air conditioner, they have 2 stage air conditioners that can be matched with a 2 stage variable speed furnace and variable fan.  Add zoning and wireless network thermostats to this unit that lets you program your thermostat over your computer and you now have the tippy top of the line.  Heat pumps are a nice option as well in the right climate.

Mine did the same thing.  Luckily it was still under warranty and they sent me a whole new one and had me just send back the broken one.