I have a single family house and last summer i remodel my kitchen and bath, and i change my furnace to new Central air. Can i claim it on my taxes?

[MichaelMc]

Unfortunately, no. Repairs and remodeling of your personal home are not tax deductible expenses. 

However, major projects of the type that you have described, which increase the value of your home or extend its useful life, are additions to the basis of your home and can decrease any possible capital gain when the home is eventually sold.

[bwa]

and i change my furnace to new Central air.

If it meets energy credit criteria for efficiency it would qualify for an energy credit.  To see if it does, you should have a Manufacturer's Certification Statement.  If not you should get one from your contractor to support the credit. Save your receipts and the Manufacturer's Certification Statement for your records.

Home Energy Credits are under the deductions and credits tab in the first category (Your Home.)  Go to Federal Taxes, then Deductions and Credits, then Explore on my own, then Your home, then home energy credits.