Scenario summary
Frozen-meal plant (TV dinners, ready-meals, IQF vegetables, frozen pastry). Production trays cycle between freezer tunnel (-30°C blast freeze) and ambient packing line. Tray surfaces accumulate ice, freezer-burn residue, food fragments from packaging stations.
The cleaning challenge
Trays often arrive at the wash bay frozen (sometimes -10°C surface temperature). Thermal shock from immediate 82°C wash can stress thin-gauge stainless. Ice removal needs to happen progressively. HACCP requires documented sanitization despite the cold starting temperature.
Recommended PTW-1900 setup
Chamber: SUS316 — frozen-food plants often use brine refrigeration and salt aerosol contaminates ambient air.
Heating: Electric 70 kW with pre-warm cycle.
PLC profiles:
- Frozen Tray Cycle 9-min — pre-rinse warm water (40°C, 60 sec), then standard wash, then 82°C rinse
- Standard 6-min — ambient-temperature trays
- Sanitization Only 8-min — daily reset
Critical accessory: Pre-warm rinse loop to bring frozen trays to ~40°C gradually before main wash, preventing thermal shock.
Expected ROI
- Labour savings: 4 wash workers → 1.5 → ~$80,000 annual
- Tray service life: thermal shock damage avoided extends tray life 2–3x
- Payback: ~7 months
Frozen food FAQ
Q: Frozen plastic trays — thermal-shock cracking? A: Pre-warm rinse prevents shock. Most food-grade plastic trays survive the gradual warm-up; thin-walled PET trays may need separate handling.
Q: Ice removal — chamber drain capacity? A: Heavy ice load drains to a 4-inch (2” standard, upgrade option) chamber drain. Heavy frozen-product plants order the upgrade.
Q: Frost on chamber interior after frozen-tray loading? A: Chamber pre-heat cycle (60-sec ambient-air warm) before tray load minimizes frost. Standard PLC profile.