TL3
Level 2

Depreciation of a central AC/furnace

I am replacing AC/furnace for my rental house (built in 1997). Should I choose 7-year depreciation or 27.5? A CPA told to use 7 year. I'd like to confirm this with other CPA's in the community! Actually 27.5 years doesn't make sense since AC/furnace can't last that long.  Thanks!