Walk-in cooler and freezer evaporator coils are the silent profit leak in nearly every food-handling operation. A coil that's lost 25% of its design airflow doesn't trip an alarm — it just runs the compressor longer, raises the case temperature a fraction of a degree, and quietly adds 15–30% to the refrigeration line on the utility bill. Dry ice cleaning is the highest-ROI maintenance scope we offer.
Why coils foul
Aluminum fin coils accumulate three things over time: airborne dust and lint, biofilm (especially in cooler service above 35°F), and ice from defrost cycles that doesn't fully sublime. Each layer reduces the surface-to-air contact that drives heat transfer. By year five, most uncleaned coils are operating 20–35% below design.
Why dry ice is the right tool
- No process water — protects the cold-zone hygiene policy and avoids re-icing during cleaning
- No bent fins — pellets clean between fins without the comb damage that brushes and pressure cause
- No chemical residue — important for direct-product-contact zones and for any FSMA-audited operation
- Documented in place — coil cleans during overnight or low-load windows without product loss
Measured energy recovery
Customers who track utility data before and after see typical recoveries of 15–30% on the refrigeration line for a 5+ year coil. On a mid-sized walk-in (5–10 kW connected refrigeration load), that's $400–$1,200 annually — well above the per-coil cleaning cost. The math gets better at multi-walk-in sites.
Cadence
Quarterly for high-load freezer evaporators and dirty production environments. Semi-annual for standard walk-ins. Annual at minimum for any coil older than 3 years.