Refrigerated shipping containers (reefers) are insulated, temperature-controlled units designed to transport and store perishable goods at precise temperatures. Unlike standard containers, they feature integrated refrigeration systems, robust insulation, and advanced climate control technology.

How Reefers Work: Core Components

1. Refrigeration Unit

• Self-contained system mounted on one end (usually front)

• Powered by three-phase electrical supply (440V/60Hz is common) or an integrated diesel generator

• Capable of cooling down to -30°C (-22°F) and heating when needed

• Includes digital controller for temperature programming

2. Insulation & Structure

• Polyurethane foam insulation in walls, floor, and ceiling

• T-shaped floor with channels for cold air circulation

• Hermetically sealed doors with dual gaskets

• Stainless steel interior for hygiene and corrosion resistance

3. Air Circulation System

• Bottom air delivery through floor channels

• Top air return through ceiling

• Creates a consistent temperature blanket around cargo

Key Specifications

Primary Applications

Transport & Storage of:

• Food Products: Fruits, vegetables, dairy, meat, seafood

• Pharmaceuticals: Vaccines, medicines requiring cold chain

• Floral Products: Cut flowers, plants

• Chemicals: Temperature-sensitive materials

• Emergency Use: Mobile morgues, temporary food banks

Common Industries:

• Agriculture & Fisheries: Harvest season overflow, processing

• Food Distribution: Temporary storage during logistics delays

• Event Management: Mobile refrigeration for large events

• Medical: COVID-19 vaccine storage, medical supply chains

Used vs. New Reefers: Considerations

Used Reefers (Most Common Purchase)

Advantages:

• 50-70% cost savings vs. new units

• Immediately available from shipping fleet turnover

• Often recently reconditioned with updated components

What to Inspect:

1. Compressor hours (like mileage on a car)

2. Condition of evaporator and condenser coils

3. Insulation integrity – check for cold spots or moisture

4. Door seal effectiveness – test with dollar bill method

5. Control system functionality – can it hold set temperature?

6. Structural rust, especially around door frames and floor

Typical Lifespan: 10-15 years in shipping, then 10+ more years in static storage with proper maintenance

New Reefers

When to Consider:

• For critical pharmaceutical storage requiring certified performance

• When warranty and reliability are paramount

• For heavy-use commercial applications where downtime is costly

Operating Considerations

Power Requirements

• Most require 3-phase power – check your facility’s capability

• Generator sets available for remote locations

• Energy consumption: 3-7 kW when running (cycles on/off)

Site Preparation

1. Level concrete pad with proper drainage

2. Adequate clearance (1m/3ft minimum) around unit for airflow

3. Electrical connection by qualified electrician

4. Accessibility for delivery (often requires crane)

Maintenance Essentials

• Regular condenser cleaning (monthly in dusty environments)

• Door gasket inspection and replacement when hardened

• Defrost system verification

• Data log review for temperature excursions

Cost Factors

Additional Costs:

• Delivery & crane service: $500 – $2,000

• Electrical hookup: $1,000 – $3,000

• Generator set (if needed): $3,000 – $8,000

• Annual maintenance: $500 – $1,500

Critical Questions Before Purchase

1. “What are the compressor hours?” (Under 15,000 is good for used units)

2. “Has it been pressure tested for insulation integrity?”

3. “What’s the service history? Any major component replacements?”

4. “Does it come with a performance guarantee?” (e.g., holds set temp for 24 hours)

5. “Are all controller functions working, including alarms and data logging?”

6. “Is the T-floor intact and clean?” (Replacement is very expensive)

Common Pitfalls to Avoid

❌ Assuming single-phase power – most reefers require 3-phase
❌ Ignoring delivery logistics – reefers are heavier and require careful handling
❌ Overlooking insulation degradation – moisture absorption reduces efficiency
❌ Buying without performance testing – always test under load if possible
❌ Underestimating operating costs – refrigeration is energy-intensive

Best Practices for Static Storage Use

1. Install temperature alarms with remote notification

2. Implement routine defrost cycles even if manual

3. Keep detailed temperature logs for compliance (food/pharma)

4. Consider a backup generator for critical applications

5. Place on proper foundation to prevent floor damage and ensure drainage

Conclusion

Refrigerated containers offer turnkey, mobile cold storage at a fraction of permanent facility costs. For most businesses, a reconditioned used reefer provides the best value, offering years of reliable service.

The key to success lies in:

1. Thorough inspection focusing on refrigeration performance

2. Proper site preparation and electrical setup

3. Regular maintenance to extend service life

Final Recommendation: Purchase from a specialized reefer supplier rather than a general container company. They understand the technical aspects and can provide meaningful performance guarantees and after-sales service for the refrigeration system.