Rental expenses are $3k more than income but net rent income just says $0 (not a loss) and looks like it had no impact on my overall refund. How do I show/claim the loss?

Thank you for choosing TurboTax. 

As per CRA: You have a rental loss if your rental expenses are more than your gross rental income. If you incur the expenses to earn income, you can deduct your rental loss against your other sources of income. Therefore it should have an impact on your refund or taxes dues whichever is applicable to you.

Please follow the steps given below.

• In the upper-right corner of your screen, select Find.
• In the Find window, type Rental Properties.
• Select Rental Properties from the list, and select Go.

Enter Income and Expenses on that page and "Press" continue. In the rental summary, you will able to see -$3000 under net income.