Did my accountant use wrong judgement in preparing my taxes for yr 09 if I desired to...

[Marvin]

...get higher depreciation.? Depreciated 27.5 yrs. The asset is a completely replaced AC/heat system in a rental house on the coast. The AC/heat system will or may have to be replaced again in 10 yrs or less. Also my question is can I start a new depreciation system replacing 27,5 years straight line with 10 yrs and 200DDB or choosing a little 179 mix-up and MARCS depreciation. The asset is $7903 cost and put in service on 11/01/09. I am doing my taxes myself (2010) this year. Thanks Marvin