First verify that the heat pump installed is eligible for the Home Energy tax credit using this website - https://www.energystar.gov/about/2016_federal_tax_credits

If eligible, then enter home energy improvement in the Search box located in the upper right of the program screen.  Click on Jump to home energy improvement

On the screen Tell Us How Much You Paid for Energy-Savings Improvements, enter the cost of heat pump in the box Energy-Efficient Building Property

The maximum dollar amount for energy-efficient building property is 10% with a credit limit up to $300.