Packaging Machine Seal Fault

Heat seal bar temperature or pressure out of specification. Packages may have incomplete seals.

Probable Causes (ranked)

• Seal bar heater element burned out — open circuit
• Thermocouple failed — reading incorrect temperature to controller
• Seal bar pressure cylinder low on air supply
• Seal bar surface contaminated with melted film residue
• Temperature controller needs auto-tune after heater element replacement

Fix Steps

1. 1 Check seal bar temperature with IR thermometer — compare to controller display reading
2. 2 Inspect heater element — measure resistance with multimeter, compare to nameplate
3. 3 Verify air supply pressure to seal cylinder — minimum 80 PSI required
4. 4 Clean seal bar surfaces — remove film buildup carefully with brass brush or scraper
5. 5 If heater was recently replaced, run auto-tune on temperature controller
6. 6 Replace thermocouple if temperature reading is erratic or significantly different from IR reading

Suggested Replacement Parts

Parts matched to fault category: Thermocouple

Prices are estimates. Verify part numbers match your equipment before ordering.

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