What is the general thickness of the insulation layer in an ice cream freezer?

Friends who run dessert shops or convenience stores have likely encountered this perplexing situation: Two ice cream freezers set at -18°C might consume 5 kWh of electricity in a day, while another uses 10 kWh. Freshly stocked ice cream retains its smooth texture in some freezers, yet constantly develops frost and hardens in others. The truth is, the thickness of the insulation layer quietly determines the outcome.

Many assume “thicker insulation is always better,” but industry veterans know that improper thickness either wastes energy and money or eats into storage space.

I. Mainstream Insulation Thickness Ranges from 50-100mm, Tailored for Specific Scenarios

No need to search endlessly—the core insulation thickness range for ice cream cabinets sits firmly between 50-100mm. However, this isn’t a fixed value. Different usage scenarios and temperature requirements call for entirely different thicknesses.

A special note: Ice cream storage requires stricter insulation standards. As many cold storage professionals share on platforms like Douyin, ice cream storage at -22°C to -25°C requires insulation layers at least 15cm (150mm) thick for optimal energy efficiency. While ice cream cabinets don’t need this thickness, ultra-low temperature models should never fall below 100mm.

II. These 4 Factors Are Crucial for Insulation Effectiveness

Many businesses focus solely on thickness when purchasing, overlooking more critical factors. A panel’s “heat retention capability” actually depends on the combined effects of thickness, material, manufacturing process, and structure—simply adding thickness isn’t always effective.

1. Greater Temperature Differences Require Thicker Panels

The core function of insulation is to block heat exchange between the interior and exterior. A greater temperature difference demands greater thickness. For example, in a 25°C indoor environment, a -18°C ice cream cabinet requires 70mm thickness. However, if placed in a 38°C outdoor stall, maintaining the same temperature requires increasing the thickness to over 90mm. This is akin to wearing a down jacket in winter: a thicker version is needed in northern regions at -20°C, while a thinner one suffices in southern areas at 5°C.

2. Mainstream PU Foam: Density Matters More Than Thickness

Almost all ice cream cabinets use rigid polyurethane (PU) foam insulation. This material boasts a closed-cell rate of up to 95% and a thermal conductivity as low as 0.018-0.024 W/(m·K), making it the “all-rounder” of insulation. However, note: PU foam density must be ≥40kg/m³; otherwise, even with sufficient thickness, internal voids will compromise insulation. Some manufacturers cut costs by using honeycomb foam instead of solid foam, reducing insulation performance by 30%. Even if labeled as 80mm thick, its actual effectiveness falls short of 50mm of high-quality PU foam.

3. Thicker Insulation for Frequent Door Openings

Convenience store ice cream cabinets, opened dozens of times daily by customers, experience rapid cold loss, requiring insulation 20mm thicker than household units. Outdoor models face not only greater temperature fluctuations but also direct sunlight and weather exposure, necessitating an additional 10-20mm thickness. Conversely, household units with low opening frequency require only 50mm of high-quality insulation. Excessive thickness unnecessarily consumes valuable storage space.

4. Preventing “Thermal Bridge Effects” Outperforms Thickening

Some ice cream cabinets fail to retain cold despite adequate thickness due to “thermal bridging.” For instance, poorly designed metal brackets or door gaskets act like “holes in an insulated suit,” allowing heat to escape directly. This explains why some manufacturers add extra insulation at metal joints—even with slightly thinner overall insulation, their performance surpasses poorly insulated, thicker products.

III. Choosing the Right Thickness Can Save Significant Electricity Costs Annually

Insulation thickness directly impacts electricity bills. A simple heat transfer formula explains why: heat transfer rate is inversely proportional to thickness. Greater thickness makes heat penetration harder, reducing the need for frequent cooling system activation and naturally lowering energy consumption.

Consider this real-world example: A convenience store’s ice cream cabinet with 70mm insulation consumed 8 kWh daily. After replacing it with a 90mm-thick cabinet of the same model, daily consumption dropped to 5.5 kWh. At a commercial rate of 1.2 yuan/kWh, annual savings amount to (8-5.5) × 365 × 1.2 = 1,095 yuan. However, note that beyond 100mm thickness, energy savings diminish marginally. For instance, a 120mm cabinet saves only an additional 0.3 kWh daily compared to a 100mm model, yet reduces storage capacity by 15%—making it counterproductive.

IV. Three Tips to Avoid “Fake Thickness” and “Poor Craftsmanship”

The industry has its share of tricks, like labeling 80mm thickness but delivering only 60mm, or meeting thickness standards with subpar foaming techniques. Here are three simple checks to identify these issues without specialized tools:

1. Weigh it: For the same capacity, heavier units are more reliable.

High-quality PU foam has greater density, naturally making it heavier. For example, two 153L ice cream cabinets: a premium model might weigh 62 jin (approx. 31.5 lbs), while a low-quality one could be only 48 jin (approx. 24.8 lbs). This lighter weight likely indicates insufficient foam density or reduced thickness.

2. Check the gap between the seal and cabinet body

Seal strips are the “auxiliary key” to insulation. They should feel springy when pressed and form a tight, gap-free seal against the cabinet when closed. Dents or bulges at cabinet corners indicate uneven foam distribution, potentially signaling gaps in the insulation layer.

3. Check surface temperature: After 2 hours of operation, the cabinet surface should show no condensation or excessive heat.

After 2 hours of operation, touch the cabinet’s exterior. If condensation (sweating) appears or it feels noticeably hot, this indicates poor insulation—either insufficient thickness or material/manufacturing issues. Under normal conditions, the cabinet surface temperature should be close to ambient temperature, feeling only slightly cool.

V. Verify These Standards to Avoid Substandard Products

Legitimate ice cream cabinets must comply with relevant standards, such as GB 4706.1 “Safety of Household and Similar Electrical Appliances” and T/CAR 12—2022 “Classification, Requirements, and Test Conditions for Ice Cream Freezers.”

While these standards do not mandate specific thicknesses, they impose clear requirements on thermal insulation performance. For instance, the heat transfer coefficient (K-value) must be sufficiently low to ensure uniform internal temperatures and energy efficiency compliance.

When purchasing, request the seller to provide test reports. Focus on the “heat transfer coefficient” and “foam density of the insulation layer.” If these two metrics meet standards, combined with the previously mentioned thickness ranges, you’ll largely avoid pitfalls.

Key takeaway: Don’t blindly prioritize insulation thickness for ice cream cabinets. Opt for 50-70mm for home use, 70-90mm for indoor commercial settings, & 90-150mm for outdoor/ultra-low temperature applications. Prioritize PU foam density and manufacturing process, then adjust based on usage scenarios. This ensures effective insulation without wasting space or electricity costs.