I will replace my A/C, which is 25 years old and probably has a SEER around
6, with a new A/C with a SEER 10 rating. I only use A/C 200 hours a year
(San Diego).

The old one is 3 ton and cools just right. Since the new A/C will be
considerably more efficient, can I buy a smaller A/C, let's say with a 2.5
ton rating?

Or, do I need to retain the 3 ton capacity but will merely see lower
operating costs due to higher efficiency?

The same logic would apply to my furnace: Can I reduce the size from 80,000
BTU to 65,000 BTU, because the new furnace will have 20% higher efficiency?
Or will I merely save money operating a new 80,000 BTU furnace?

My logic is a bit challenged due to my lack of knowledge.

Thanks for your help
--
Walter
www.rationality.net
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