Place the potatoes in the inner pot and add 1 cup water, 1/4 teaspoon salt, and 1/4 teaspoon pepper. Place a steam rack on top of the potatoes.
On top of the salmon add the paprika, lemon zest, 1/2 teaspoon salt, and 1/4 teaspoon pepper and place the salmon on top of the steam rack. Secure the lid.
Press the Manual or Pressure Cook button and adjust the time to 3 minutes.
When the timer beeps, let pressure release naturally until float valve drops and then unlock lid.
Remove the salmon and steam rack from the pot and set aside.
Press the Sauté button and cook the potatoes 1 minute. Add the garlic and cook an additional 2 minutes, stirring frequently. Stir in the oil and the remaining salt and pepper. Use a fork to gently mash the potatoes to achieve a chunky texture. Press the Cancel button.
Add the spinach and stir until wilted, about 1–2 minutes. Serve the salmon and potato and spinach mixture with the lemon wedges.