Had to choose between fixing my old AC unit or getting a whole new system. Picked the new one and my power bill dropped $150 last month. | Atlanta Homeowners - The Community Guide
You said "old unit" but I don't think it was a unit at all. That drop was for a whole different service tier, not just replacing one piece of hardware. The old price was for a much more basic plan. So the big drop makes sense when you see you're comparing two totally different things.