In the commercial refrigeration industry, manufacturers face a fundamental design choice: do you cut manufacturing costs to lower the upfront price, or do you invest in engineering to achieve extreme energy efficiency and superior food preservation?

Most commercial cake showcases on the market take the shortcut. They use a small evaporator paired with a high-displacement compressor—saving on copper tubing costs while relying on raw compressor power to force temperatures down.

When we launched our new 2-meter commercial cake showcase, many refrigeration engineers and clients asked the exact same question:

“Why use a compressor with a displacement of only 6.3cc (Embraco VEMT406U) in such a large 2-meter showcase, while making the evaporator unusually large?”

Today, we are breaking down the engineering philosophy behind this system optimization and inviting industry peers and clients to weigh in.

1. Core Engineering: Why “Large Evaporator + Small Displacement”?

In traditional commercial showcase designs, the Temperature Difference (TD) between the evaporator and the cabinet air is typically around 8∘C to 12∘C or higher. A large TD causes extremely low evaporation temperatures, rapid frost accumulation, severe dehumidification, and a sharp drop in compressor Coefficient of Performance (COP).

By significantly increasing the heat exchange surface area of the evaporator and pairing it with a Sanhua Electronic Expansion Valve (EEV) for precise, millisecond-level refrigerant flow control, we achieved a critical breakthrough:

A Temperature Difference (TD) of Only 2∘C

To maintain a cabinet temperature of 2∘C, a traditional system might require an evaporating temperature as low as −10∘C. Our optimized system maintains a 2∘C cabinet temperature with an evaporating temperature as high as 0∘C.

• Reduced Compressor Work: Every 1∘C increase in evaporating temperature boosts compressor efficiency by roughly 3% to 4%.
• High Efficiency with Small Displacement: Powered by the Embraco VEMT406U variable-capacity compressor (6.3cc displacement), the unit effortlessly cools a 2-meter cabinet while running at peak efficiency.

2. Superior Product Preservation: Beyond Energy Savings

For bakeries, cafes, and high-end supermarkets, a display cabinet is not just for cold storage—it is designed to preserve freshness and presentation. Our large-evaporator system delivers two crucial operational benefits:

High Humidity Retention (77% – 85% RH)

Large temperature differences strip moisture from the air, causing cakes to dry out, cream to crack, and fresh foods to lose visual appeal. A minimal 2∘C TD prevents moisture loss, naturally maintaining 77% to 85% relative humidity inside the cabinet to extend shelf life and preserve product appearance.

Defrost Temperature Stability (Food Temp Stays Below 5∘C)

During defrost cycles, standard showcases often experience temperature spikes above 10∘C, which degrades delicate whipped cream and encourages bacterial growth. Thanks to the thermal mass of our large evaporator and precise metering from the Sanhua EEV:

• Operating Range: Cabinet temperature stays consistently within −2∘C to 5∘C.
• Zero Spikes During Defrost: Even during active defrost cycles, the actual temperature of stored food items does not exceed 5∘C.

3. The Economics: Only 7 kWh per 24 Hours

For commercial operators, the purchase price represents only a fraction of the total cost of ownership (TCO). Operating electricity costs represent the real long-term expense.

• Standard 2m Cake Showcase: Consumes between 12 to 18 kWh/day.
• Our Optimized Showcase: Tested at only 7 kWh per 24 hours under standard commercial operating conditions.

This represents an energy reduction of nearly 40% to 60%, saving operators hundreds of dollars annually per unit and allowing the initial investment in premium engineering to pay for itself quickly.

4. Join the Discussion: Calling All Refrigeration Engineers

Engineering excellence is a continuous process. Combining a large-surface evaporator, a Sanhua electronic expansion valve, and a small-displacement variable-speed Embraco compressor is our answer to the demand for extreme efficiency and uncompromising quality.

• How do you evaluate this system layout for your commercial projects?
• In high-ambient or high-humidity environments, what superheat control strategies would you recommend for further tuning the EEV?

We welcome comments, feedback, and technical insights from HVAC/R engineers, industry peers, and commercial kitchen designers below!