Setting the temperature in a refrigerated display case: instructions, norms and secrets of professionals

A refrigerated display case is a key element for a business related to the storage and display of products. Incorrectly set temperatures can lead to product spoilage, increased energy consumption, or even equipment failure. In this article, we will look at how to correctly set the temperature regime in display cases of different types, taking into account the design features, workload and range of products.

Showcases differ from household refrigerators not only in size, but also in the cooling system, cold air distribution, and ventilation requirements. For example, open display cases (with transparent glass facades) lose up to 30% of the cold due to constant contact with the environment, so their setup requires a special approach. Closed models with doors are more energy efficient, but there are also nuances here - from the location of sensors to the zoning of temperature conditions.

We have collected current recommendations from manufacturers (Lieberr, Polar, Snaige), SanPiN standards for food storage, as well as advice from service engineers. If you are the owner of a store, a cafe, or simply use a display case for home needs, these instructions will help you avoid common mistakes and extend the life of your equipment.

Types of refrigerated display cases and their features

Before adjusting the temperature, it is important to understand what kind of display case you are working with. This affects the range of available settings, cooling speed, and even the location of controls. Here are the main categories:

• 🔹 Open display cases — without doors, with constant air circulation. Used to demonstrate drinks, dairy products, and semi-finished products. They require a lower temperature due to heat loss.
• 🔹 Closed display cases —with sliding or hinged doors. Suitable for meat, fish, delicacies. More energy efficient, but require regular defrosting.
• 🔹 Showcases with forced ventilation —equipped with fans for uniform distribution of cold. Optimal for high display cases (above 1.5 m).
• 🔹 Low temperature displays - support the mode down to −18°C for ice cream, frozen products.
• 🔹 Hybrid models - combine zones with different temperatures (for example, +2...+6°C for milk and 0...−2°C for meat).

Manufacturers often indicate climate class showcases (for example, SN-T or N-ST). It shows at what ambient temperature the equipment will work effectively. For example, a class showcase T is designed for +18...+43°C, and one for +10...+32°C. If the room is hotter or colder than normal, the compressor will work hard, and the temperature inside the display case will “float”. SN — at +10…+32°C. If the room is hotter or colder than normal, the compressor will work hard, and the temperature inside the display case will “float”.

Optimal temperature conditions for different products

SanPiN 2.3.2.1324-03 and technical regulations of the Customs Union clearly regulate the storage conditions of food products. Violation of these standards can lead not only to damage to the goods, but also to fines during inspections. Below is a table with recommended ranges for the most common categories:

Critical error: storing meat and fish at temperatures above +4°C accelerates the growth of bacteria Salmonella and Listeria by 2-3 times. This is especially true for open display cases, where products come into contact with the air in the room. If the display case is used for several types of products, divide them into zones or use hybrid models with independent adjustment.

For ice cream and For frozen foods, the temperature should not exceed −18°C. At −12°C, the shelf life is reduced by 2 times, and the quality (texture, taste) deteriorates. Modern low-temperature display cases (Lieberr VN-120, Polar FZ-200) are equipped with a system No Frostthat prevents the formation of ice without manual defrosting.

Step-by-step instructions: how to adjust the temperature

The setting algorithm depends on the model of the display case, but the general sequence of actions is the same. Below is a universal instruction taking into account the nuances for different brands.

Disconnect the display case from the network for 5-10 minutes (to reset errors)

Make sure that the products are distributed evenly (do not block ventilation)

Check the door seals (for closed showcases)

Clean the temperature sensors from ice/dust-->

1. Access to the control panel

In most showcases, the controls are located:

• 📍 On the top panel (for example, Snaige V-140 —the buttons are hidden under a removable cover).
• 📍 On the inside of the door (showcases Polar series HC).
• 📍 On a digital display with touch buttons (Lieberr models ECO).

If the panel does not respond to touch, check:

• 🔌 Connection to the network (the power indicator should be on green/blue).
• 🔒 Lock mode (some models have protection against accidental pressing - hold Lock 3 seconds).

2. Temperature adjustment

Setting methods depend on the type of control:

• 🔢 Mechanical control (rotary control): turn the knob to the side + to increase the temperature, − to decrease the temperature. The step is usually 1-2°C.
• 📱 Electronic control:
  1. Press Mode or Set to enter the menu.
  2. Use the ↑/↓ buttons to select a parameter Temperature.
  3. Set the desired value (for example, +4°C).
  4. Save the settings with the OK or Save.

In storefronts with multi-zone. cooling (for example, Lieberr MultiFresh), the settings are carried out separately for each section. For this:

1. Select a zone with the button Zone 1/2/3.
2. Set the temperature for each (for example, Zone 1: +2°C, Zone 2: −1°C).
3. Activate mode Smart Cooling (if available) for automatic balancing.

3. adjustment

After setting, wait 2-3 hours until the temperature stabilizes. To control:

• 🌡️ Use a separate thermometer (the error of the built-in sensors can reach ±1°C).
• 📊 Check the uniformity of cooling at different points of the display case (especially in the corners). zones).

If the temperature does not correspond to the set one:

• 🔧 Make sure that the display case is not overloaded (air circulation should be free).
• 🔧 Check the operation of the fans (in models with forced cooling).
• 🔧 Clean the condenser from dust (usually located on the back wall).
What to do if the temperature “floats”

If, after setting, the temperature rises and falls, the problem may be:

1. Faulty thermostat (replacement required).
2. Freon leak (needs a technician).
3. Contamination of the capillary tube (cleaning a specialist).
4. Unstable voltage in the network (use a stabilizer).

Common errors during setup

Even experienced users sometimes make mistakes that lead to excessive consumption of electricity or damage to products. Here are the most common of them:

• ❌ Ignoring the climate class. A class showcase N (+16...+32°C) will not cope with the heat of +35°C - the compressor will work without stopping, and the temperature inside will rise.
• ❌ Overloading of the display case. If products block the ventilation holes, the cold does not circulate, and some of the products overheat.
• ❌ Setting on the top shelf. In open display cases, the warmest zone is the top (due to the rise of warm air). Measure the temperature in the middle part.
• ❌ Frequent opening of doors. In closed display cases, each opening increases the temperature by 1–2°C. Use models with automatic closing.
• ❌ Neglecting defrosting. Ice on the evaporator worsens heat transfer, and the display case begins to “fall short” of the set parameters.

⚠️ Attention: If the display case is connected to the SMARTmonitoring system (for example, Lieberr Connect), do not turn it off from the Internet. If the connection fails, some models reset the settings to factory settings.

Another typical problem is condensation on glass open display cases. It appears due to high humidity in the room or incorrect settings anti-fog. In most models (Polar, Snaige), this function can be enabled separately in the menu Options → Anti-Fog.

Setting features for popular brands

Each manufacturer makes its own adjustments to control system. Let's consider the nuances for the most common brands.

Lieberr

The display cases of this brand are equipped with a system EcoSmartthat automatically adjusts the operation of the compressor to the load. To manually change the temperature:

1. Click Menu → Temperature Control.
2. Select a zone (if the showcase is multi-zone).
3. Set the value in 0.5°C steps (range: −20°C to +10°C).
4. Save the settings button OK.

For models with display TouchControl (for example, Lieberr VN-180) a function is available Quick Cool —accelerated cooling to −2°C in 30 minutes.

Polar

In showcases Polar series HC i FZ the temperature is regulated by a rotary switch with marks from 1 (maximum cold) to 7 (minimum). Correspondence of marks and temperature:

• 1–2: −18...−12°C (for freezer display cases).
• 3–4: 0...+2°C (meat, fish).
• 5–6: +4...+6°C (dairy products).

For To reset the settings to factory settings, hold the button Reset 5 seconds.

Snaige

The display cases Snaige are distinguished by simple mechanical adjustment, but in the latest models (Snaige V-140N) an electronic unit has appeared. To change the temperature:

1. Press Set and hold for 3 seconds.
2. Use the +/− buttons to set the value (1°C step).
3. Confirm by pressing Set.

Attention: in showcases Snaige with by the system AirFlow when the temperature changes, the fan speed is automatically adjusted.

⚠️ Attention: In the instructions for display cases Polar i Snaige sometimes outdated mode designations are indicated. For current data, see the official website or product data sheet.

Energy saving: how to reduce energy consumption

Refrigerated display cases consume up to 30% of all electricity in a store or cafe. Optimizing settings will help reduce costs by 10–25%. Here are proven methods:

• 💡 Night mode. Lower the temperature by 1–2°C during closing (for example, from +4°C to +5°C).
• 💡 Closed curtains. For open display cases, use transparent plastic curtains at night - this reduces heat loss by 15%.
• 💡 Regular defrosting. Ice on the evaporator increases the load on the compressor by 20-30%.
• 💡 Optimal loading. The display case is 70-80% full. Empty or overloaded - wastes more energy.
• 💡 Clean condenser. Dust on the rear grille impairs heat transfer. Clean it every 2 months.

Modern display cases (Lieberr EcoPro, Polar GreenLine) equipped inverter compressorsthat automatically adjust power to the load. In such models, energy consumption is 40% lower than conventional ones.

Another way to save is use a timerIf the display case does not operate around the clock (for example, in cafe), set it to turn off during non-working hours. To do this:

1. Connect the display via socket timer.
2. Set the operating interval (for example, from 8:00 to 22:00).
3. Before turning off, make sure that the products will not spoil during downtime.

Fault diagnosis by temperature failures

If the display case does not maintain the set temperature, this may be a symptom of a serious breakdown. Let's consider typical "symptoms" and their causes:

Problem	Possible cause	Solution
The temperature is higher than normal, the compressor is running non-stop	Freon leak, capillary tube clogged	Call a technician for refilling or cleaning
The temperature fluctuates (either +2°C or +8°C)	The thermostat or sensor is faulty	Replacing the sensor or control board
The display case does not cool, the compressor does not turn on	The starting relay is burned out, the compressor winding is broken	Diagnostics with a multimeter, replacement of the relay/compressor
There is a lot of ice on the back wall, the temperature is normal	Clogged drainage hole or faulty defrost heating element	Cleaning the drainage or replacing the heating element
The display case makes a lot of noise, but does not cool	Wear of fan or compressor bearings	Lubricating or replacing bearings

For initial diagnostics:

1. Check whether the indicator is on power.
2. Put your hand on the compressor (it should vibrate and be warm).
3. Listen to see if the fan is working (in models with forced cooling).

⚠️ Attention: If the display case is under warranty, do not disassemble it yourself (Lieberr, Polar) will void the warranty if tampered with the cooling system.

FAQ: answers to frequently asked questions

How often do you need to defrost the display case?

Depends on the type of system:

• 🔹 No Frost — once every 6–12 months (for cleaning from dust).
• 🔹 Drip system — once every 1–2 months.
• 🔹 Manual defrosting —when ice forms more than 5 mm thick.

To speed up the process, use a fan or containers with warm water (but do not place them on shelves!).

Is it possible to use a household thermometer to check the temperature?

Yes, but with reservations:

• 🔹 A household thermometer should be alcohol (mercury is prohibited in food areas).
• 🔹 The error should not exceed ±1°C.
• 🔹 Measure the temperature in several points (top, middle, bottom).

For professional control, use temperature loggers (for example, Testo 174T), which record data every 10 minutes.

Why do products freeze slightly in an open display case, although the temperature is set to +4°C?
This is a typical problem for display cases with forced ventilation. Cold air blows directly on the products located near the ventilation holes.
• 🔹 Move sensitive foods (milk, greens) away from fans.
• 🔹 Reduce the ventilation speed in the menu (if there is an option Fan Speed).
• 🔹 Use protective screens made of plastic to direct air flow.
Do I need to turn off the display case at night?

Depends on the type of products and the climate class of the display case:

• 🔹 For meat/fish — you cannot turn it off (risk of bacterial growth).
• 🔹 For drinks/dairy products —you can turn off for 4–6 hours if the room temperature is not higher than +20°C.
• 🔹 For ice cream - turning off is unacceptable (thawing will ruin the texture).

If you decide to turn it off, use timer and make sure that the display case has time to restore the temperature before opening.

How to set the temperature if there are no instructions?

Follow the universal algorithm:

1. Find the temperature regulator (usually indicated Temp, Cold or a snowflake ❄️).
2. If the regulator is mechanical, turn it 1 notch and wait 2 hours.
3. Check the temperature with a thermometer.
4. If necessary, adjust by another 0.5–1°C.

For electronic panels:

1. Look for the buttons Set, Mode or Temp.
2. Press them one by one until you find the temperature menu.
3. Set a value close to the standard one for your products (see table above).

If that doesn’t work, take a photo of the control panel and look for the model of the display case using the sticker on the back wall. Usually there is an indication model numberwhere you can find instructions on the Internet.