Do not open the lid yet
. Wait 5 to 20 minutes until the air vent is down, which indicates there's no more pressure, then remove the lid. Place a meat thermometer into the center of the roast to make sure it's cooked thoroughly. The meat should be at least 170 degrees Fahrenheit. If it isn't, place the lid back on and let the cooker pressurize again and cook longer. Check it every 15 minutes until reaches 170 degrees. Once the roast is fully cooked, turn the pressure cooker off and let the meat sit for 10 minutes before serving.
Tip
The cooked roast may be a little tougher than meat that was thawed first.
References
Daniel Glover; Chef; Palm Beach, Florida Presto: Presto Electric Pressure Cooker Instruction Manual