my presto 01362 pressure cooker won't pressurize, lid keeps hissing

Diagnosis

The persistent hissing indicates steam is escaping from the lid instead of building pressure. This is almost always due to a failed seal or an incorrectly seated component. The two most common culprits are the pressure regulator (weight) not being properly placed on the vent pipe or a damaged, dirty, or misaligned silicone sealing ring (gasket).

How to Fix It

First, ensure the cooker is cool and unlocked.

1. Remove the pressure regulator from the vent pipe. Check that the vent pipe itself is clean and unobstructed.
2. Re-seat the pressure regulator: Place it directly onto the vent pipe so it sits level. The older "jiggler" type should wiggle freely; a newer weighted type should sit flat.
3. Inspect the black silicone sealing ring (Presto part #09936). Remove it from the lid's groove. Check for permanent folds, cracks, brittleness, or tears.
4. Clean the ring and the groove thoroughly with warm, soapy water to remove any food particles or grease that could break the seal. Dry completely.
5. Reinstall the sealing ring, ensuring it is seated evenly all the way around its groove with no twists or kinks.
6. Before cooking, perform a leak check: Add 2 cups of water, lock the lid, and heat on high without the regulator. Steam should only come from the vent pipe. Once a steady stream forms, place the regulator on. The hissing should stop as pressure builds and the regulator begins to rock/jiggle.

If That Didn't Work

If the hissing continues after the above steps, inspect the lid's over-pressure plug (a rubber button on the lid). Ensure it is clean and seated correctly. Also, check the bottom of the pressure regulator for mineral deposits or food debris and clean it. Finally, examine the cooker body's rim and the underside of the lid for any dents, warping, or debris that could prevent a tight seal. A worn-out sealing ring often needs replacement, even if no damage is visible; they degrade with heat and time.

Heads Up

Never force the lid closed if it doesn't lock easily—this indicates misalignment. Always ensure the lid is properly aligned and locked before attempting to pressurize. A damaged sealing ring or lid must be replaced; do not operate the cooker if it cannot seal properly.