TL;DR

A door seal leak drops retort pressure below the process specification and compromises the sterilization process. Inspect the gasket and groove before replacing the seal.

What you might see

steam or hot water escaping around door perimeter
vessel pressure falling below setpoint during process
door seal alarm on control panel
visible damage or debris in door gasket groove

Likely causes

Tap to mark as ruled out

Gasket compression set or cracking from thermal cycling
Food product or label residue in the gasket groove preventing full sealing
Door closure mechanism not generating sufficient clamping force
Gasket material incompatibility with cleaning chemicals used in CIP

Required tools

Calipers
LOTO kit
Lint-free cloths
Replacement gasket (food-grade material)

Safety first

Retort vessels operate with steam at elevated pressure. Confirm pressure is at zero before opening the door or working on the door seal.
Hot food product may remain in the vessel after a cycle. Wear thermal gloves and splash protection when draining.
Any retort cycle that failed to achieve the specified process value (Fo) requires a product hold and disposition per food safety procedures.

Procedure

7 steps · ~30 min

1
Complete the current cycle or abort safely and de-pressurize the vessel. Confirm pressure is at zero.
Warning: Retort vessels operate at elevated steam pressure, typically 1 to 2 barg. Never approach the door while the vessel is pressurized.
2
Lock out the steam supply and door actuator power.[1]
3
Open the door and inspect the gasket and groove. Remove any food product, label stock, or residue from the groove.[1]
4
Inspect the gasket for compression set, cracking, or tears. A gasket with compression set will not recover to full sealing height.
5
Verify the door closure mechanism torque or hydraulic pressure is within the specified range.
6
Replace the gasket if damaged. Install the new gasket per the general installation procedure, seating it without twisting.
7
Run a door pressure hold test before returning to production.

Sources

Allpax (ProMach) Allpax Shaka / Steam Air Retort / Sterilizer general technical documentation, Allpax (ProMach)
Allpax Shaka / Steam Air retort general door seal inspection and replacement procedures (general)

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