Professional refrigeration equipment of the brand Polair is deservedly in high demand in the HoReCa segment due to its reliability and ability to operate in a wide temperature range. However, like any complex technical unit, these machines require proper initial setup to ensure a stable microclimate inside the chambers. The correct configuration of the controller is not just a formality, but a necessary condition for the safety of products and long service life of the compressor.
Shop and restaurant owners are often faced with a situation where the factory settings do not meet the specific storage requirements of specific goods. For example, meat and dairy products require different temperature conditions. In this material, we will analyze in detail the algorithms for setting up electronic control units, methods for calibrating sensors and ways to eliminate common failures.
Before you start manipulating the buttons, it is important to understand that modern models Polair are equipped with complex electronics that are sensitive to power surges. Any adjustment should be made only after the equipment has completely defrosted and returned to operating mode. This will avoid false sensor readings and incorrect operation of the automation at the time of initial startup.
Electronic controller control
The central control element in refrigerators Polair is an electronic controller, most often brand Carel or Evco. The front panel of such a device is usually equipped with a digital display and a set of buttons that allow you to interact with the “brain” of the unit. The user's main task is to learn how to read current readings and switch between data display modes.
In normal operation mode, the screen displays the current temperature inside the chamber. However, by pressing a certain key combination, you can see the set value (setpoint) that the system is aiming for. The difference between the actual temperature and the setpoint is called delta, and it is this that determines the on and off cycles of the compressor. Understanding this logic is critical for accurate tuning.
⚠️ Attention: Pressing the buttons for a long time (more than 5 seconds) can put the controller into parameter programming mode, which without knowing the access codes can reset the factory settings. Be careful when you first get acquainted with the control panel.
The “Set” or “Funct” button is usually used to navigate through the menu. A short press allows you to view the setting, and a long press (3-5 seconds) allows you to enter the parameters menu. Some models use the up or down arrow button to confirm a selection, while others press Set again. Interfaces may differ depending on the year of manufacture of the equipment.
Adjusting temperature settings
The most common operation required from the user is changing the target temperature. The setup process setpoints is quite simple, but requires a sequence of actions. First, you need to briefly press the set button (often indicated as “Set”), after which the current value of the temperature that the refrigerator is aiming for will flash on the display.
Using the Up and Down arrow buttons, the user can change this value. Setting values outside the recommended ranges may result in evaporator freezing or product damage.
After selecting the desired value, you must confirm the change by pressing the “Set” button again or waiting for the menu to automatically exit (usually after 10-15 seconds). The system will immediately begin to work out the new algorithm, however, the real change in temperature inside the chamber will not occur instantly, but after 20-40 minutes of compressor operation.
☑️ Checking the temperature setting
Setting differential and hysteresis
To fine-tune the operation of the refrigerator, you need to understand the parameters differential (Differential) and hysteresis. These terms refer to the temperature difference between turning the compressor on and off. If this parameter is not set correctly, the unit will either work without interruption or turn on too often, which leads to wear and tear on the equipment.
Consider an example: if the setpoint is set to +4°C and the differential is 2 degrees, the compressor will turn off when it reaches +4°C, and will turn on again when the temperature rises to +6°C. Too small a differential (less than 1 degree) causes the compressor to “clock,” which is harmful to the electrics. Too high (more than 5-6 degrees) will lead to fluctuations in the temperature of the products, which is unacceptable for perishable food.
Changing these parameters is usually hidden in the deeper level menu, accessible only through a password or a long combination of buttons. The tables below show typical values for various controller parameters Evco and Carelthat are often found in technology Polair.
| Parameter | Designation | Typical value | Description influence |
|---|---|---|---|
| Set Point | St | +4.0°C | Target cooling temperature |
| Differential | df | 2.0°C | On/off temperature difference |
| Max Temp | Mx | +10.0°C | Maximum permissible setting |
| Min Temp | Mn | -10.0°C | Minimum permissible setting |
| Compressor Delay | cd | 6 min | Restart delay |
It is worth noting that changing the differential unnecessarily is not recommended. Factory settings, as a rule, are already optimized by engineers Polair for the thermal characteristics of a specific cabinet model. Intervention makes sense only for specific storage requirements or when replacing the thermostat with an analogue with different characteristics.
Defrosting (defrosting) modes
Automatic defrosting is a key process for maintaining the efficiency of the heat exchanger. In refrigerators Polair the most often used method is defrosting with air heat (natural) or electric heating elements. Setting the frequency and duration of this process is critically important: infrequent defrosting will lead to the evaporator becoming overgrown with a fur coat, and too frequent defrosting will lead to an unnecessary increase in temperature in the chamber. Defrosting parameters are usually designated as (interval) and (duration). The interval is specified in compressor operating hours (for example, every 6 or 8 hours), and the duration is specified in minutes. If you notice that the refrigerator has stopped cooling and ice is visible on the back wall, the defrosting parameters may be off or the defrost sensor is faulty.
Defrosting parameters are usually designated as id (interval) and Md (duration). The interval is specified in compressor operating hours (for example, every 6 or 8 hours), and the duration is specified in minutes. If you notice that the refrigerator has stopped cooling and ice is visible on the back wall, the defrosting parameters may be off or the defrost sensor is faulty.
What is a drip system in Polair?
Some Polair models use a “crying” evaporator, where defrosting occurs every time the compressor is turned off. In such systems, setting defrosting intervals is not required, since the process occurs continuously during the cooling cycle.
There is also an option to turn off the fan during defrosting. If the fan blows while the evaporator is heating, hot air will enter the chamber and food may spoil. Make sure that the function of stopping the fan during the defrosting cycle is activated in the controller menu. This is a standard setting for most models with forced circulation.
⚠️ Attention: During manual defrosting (if the automation has failed), it is strictly forbidden to use sharp objects to chip ice or direct a stream of hot air from a hairdryer directly to plastic elements and sensors. This can lead to irreversible damage to the equipment.
Diagnostics and error codes
Modern electronics Polair continuously monitors the state of the system and displays error codes when anomalies are detected. The most common of them are related to malfunctioning temperature sensors. For example, a flashing indicator or an inscription E1, E2 often indicates an open or short circuit in the temperature sensor circuit.
If you see an error code, the first thing you need to do is check the integrity of the wires going to the sensor. Sometimes the problem lies in oxidized contacts or mechanical damage to the cable. In some cases, rebooting the controller helps: disconnecting the device from the network for 1-2 minutes and turning it on again. If the error returns, the sensor element must be replaced.
Another type of error is associated with high or low pressure, although this is less common in household controllers. This may require checking the capacitor, the cleanliness of the condenser grid and the serviceability of the blower fan. A dirty condenser is a common cause of overheating and thermal protection of the compressor, which can also be displayed as a system error.
Calibration of temperature readings
Sometimes situations arise when the readings on the controller display diverge from the readings of an independent thermometer placed inside the chamber. A difference of 1-2 degrees is acceptable, but if it is larger, calibration is required. In the controller menu Evco and Carel there is a correction parameter, often designated as oF (Offset) or SC (Scale Correction).
To calibrate, place the reference thermometer in the center of the chamber, close the door and wait until the temperature stabilizes. Compare the readings. If the display shows +5°C and the thermometer shows +7°C, you must enter a correction of -2 degrees in the corresponding menu parameter. After this, the controller will take this error into account when controlling the compressor.
It is important to carry out calibration only after the refrigerator has been operating continuously for several hours. Immediately after loading warm food or after defrosting, the readings may be unstable, and adjustment at this point will lead to errors in further operation. The accuracy of calibration directly affects the safety of expensive inventory.
Why can a sensor lie?
Temperature sensors can “age” over time, changing their resistance. The installation location also affects the readings: if the sensor touches a metal wall or is close to the fan, its readings will be distorted.
Frequently asked questions (FAQ)
Why does the Polair refrigerator not maintain the temperature and constantly work?
This can be caused by several reasons: the door is not closed tightly (check the seal), The heat load is too high (a lot of warm food is loaded), the condenser is dirty (dust and dirt interfere with heat transfer) or there is a refrigerant leak. Also check the differential settings.
How to reset the controller settings to factory settings?
The reset procedure depends on the controller model. Usually you need to hold down a combination of buttons (for example, up arrow + Set) with the power off or find the “Factory Reset” option in the menu. Be careful: after the reset, you will have to re-enter all temperature settings.
What does a flashing fan light mean?
Flashing often indicates a malfunction of the fan itself or its power circuit. On some models, this may also indicate that a defrost cycle is in progress and the fan is programmed to stop. Check if the blade rotates when the door is open (in operating mode).
Is it possible to set a Polair refrigerator to freeze if it is medium-temperature?
No, by design, medium-temperature cabinets are not designed for deep freezing. An attempt to set a temperature of -18°C on a unit designed for +4°C will result in the compressor running non-stop, overheating and failure. For freezing, low-temperature models are needed.