Permissible temperature for air conditioner operation

Air conditioning systems can operate in multiple modes depending on the device of the external and internal units, the program, and temperature settings. These modes include cooling and heating the air. The specific temperature at which a program starts will determine the degree of heating or cooling. Therefore, when deciding at what temperature to turn on the air conditioner, it is important to refer to the original equipment and intended use of the system. The material below provides information on the recommended outdoor temperature for different types of split-system air conditioners.

Principle of operation of climatic systems

The fundamental principle of how any air conditioning system works relies on the characteristics of liquids, specifically their ability to absorb heat when they evaporate and release heat when they condense. All air conditioners that are designed for cooling follow a similar design with slight variations that are patented by the specific brand. The principle of operation for climate equipment that is designed for heating is also similar.

For cooling

• Initially, the evaporator supplies the compressor with gaseous Freon, which has a temperature of -20 degrees Celsius and a pressure of 5 atm;
• Once in the compressor, the Freon is compressed to 25 atm, causing its temperature to rise to 90 degrees before being transferred to the condenser;
• In the condenser, the Freon is cooled by the surrounding air, causing it to change from a gaseous state to a liquid state and release heat, as the air temperature is lower than 90 degrees;
• The warm liquid then flows through the thermostatic regulating valve, a spiral-shaped copper tube, where the Freon finally cools down, its pressure decreases, and some of the substance turns back into a gaseous state at the outlet;
• After that, the combination of gas and liquid enters the evaporator, where it is exposed to air from the surrounding area. This causes the Freon to fully convert into vapor while extracting heat from the air.

Next, the entire vapor is directed to the compressor inlet, initiating the cycle once more. This is the functioning principle of all residential air conditioning systems when it comes to cooling.

Heating

The air-conditioning system design, which also incorporates heating, is comprised of similar components, with the addition of a four-way valve. This valve allows for the reversal of freon supply and movement, thereby exchanging the roles of the condenser and evaporator.

Important! When it comes to heating the space, the evaporator and condenser serve the same functions as they do for cooling. However, in this case, the indoor unit heats the air, while the outdoor unit cools it and releases it into the atmosphere.

Temperature Limits

All air conditioners have specific temperature limits for cooling and heating. In the summer, the recommended temperature range for cooling is typically between +20 to +27 degrees Celsius. This range ensures that the system’s components are not overstrained. It is particularly important to follow this guideline for the compressor, as severe operating conditions can lead to premature wear and failure.

Depending on the brand and model, split-system air conditioners may have different temperature limits for operation. Some models may have wider temperature ranges and can also be used in rainy conditions. Users should refer to the device’s instruction manual to determine the specific temperature ranges and application options for their particular air conditioner.

In winter

It is possible to use air conditioning systems during winter, as long as the minimum temperature requirement of up to -5 degrees Celsius is met. Most manufacturers of standard systems allow for the activation of heating devices without risking excessive pressure on the compressor when the outdoor thermometer reaches these conditions.

By the way! However, there are exceptions with DAIKIN or Mitsubishi split systems. These belong to a more expensive segment that offers an extended range of operating temperatures. For instance, they can effectively heat a room even when the temperature outside is as low as -25 degrees.

In summer

The cooling process of the air in the living room during the summer happens within a broader operational span. The models in the majority of standard series have the capability to function at higher temperatures up to +45 degrees. The precision technology excels in this aspect as it can run throughout the year in a pre-set mode with an accuracy of temperature control up to 0.5 degrees.

Consequences of operating the system at prohibited temperatures

If the manufacturer’s recommendations regarding the maximum allowable temperatures are disregarded when operating climate control equipment, there is a risk of experiencing critical malfunctions. The manufacturer also explicitly states in the safety precautions why systems that are not designed for winter operation should not be used. Here’s a breakdown of what can happen if these restrictions are not followed:

• The equipment’s efficiency may be reduced, ultimately resulting in a complete shutdown.
• Icing can occur on both the outdoor and indoor units.
• The oil in the refrigerant may become thicker.
• Parts may experience excessive friction due to lack of lubrication.
• The drain tube can become blocked with ice.
• Condensation may leak into the living space.
• The fan blades may break.
• The compressor may experience wear and eventually break.

Attention! The majority of split-systems are intended for functioning at typical yearly temperatures. They can serve as auxiliary heat during the non-heating season until the primary heat source is activated, but not beyond that.

Switching on the air conditioner in winter for cooling

Given that the majority of air conditioners operate on the same principle, it is prohibited to use the climate equipment for cooling purposes in low temperatures. Thus, the ability to enable cooling during winter is only feasible if the temperature falls within the range specified by the manufacturer. In most instances, this range is not less than -5 degrees Celsius.

If cooling is necessary at temperatures below -5 degrees, such as for server rooms, a specialized system is required. Otherwise, the air conditioner will malfunction – the compressor will overheat and become damaged. Specific details should be directly confirmed in the user manual for the respective device.

Why split-system is not switched on for heating

If your air conditioner is not producing heat, it’s possible that the issue is not a malfunction, but rather that the temperature outside is outside the acceptable range for the compressor to generate sufficient heat. In such cases, the device will only be able to raise the indoor temperature by 1-3 degrees.

Important! The most optimal temperature range for using an air conditioning system to heat a room is between 0 and +5 degrees Celsius.

If the split system is designed for heating and equipped with a winter set, if the air coming from the indoor unit is not warm, the issue may be due to a faulty valve. The valve is responsible for regulating the operation modes of the air conditioner for "winter" and "summer". To resolve this problem, please contact the service center.

Another possible cause for the absence of warm air from the air conditioner is a malfunctioning compressor. You may suspect a compressor malfunction if the equipment does not start, but air is still coming out of the unit. In this case, it is also necessary to call a professional technician.

Sometimes, the unit simply needs to run for 15 minutes in order to heat the air. This process is known as the defrosting mode, which allows the device to adjust after the power is turned on. If this is the case, it is important to know how to activate the air conditioner for heating.

What is a winter kit

A winter package is a collection of various components that enhance the functionality of an air conditioner. This package consists of:

• compressor crankcase heater;
• drainage hose;
• electronic board.

By utilizing this collection, the split-system is able to operate in heat even when temperatures are exceptionally low. However, it is imperative to comprehend that despite the expanded assortment, the conditioner is still not suitable for heating the room during the winter season.

What split-systems are designed for heating in winter

In order to achieve optimal heating in an apartment or house, a simple air conditioner with a winter set is not sufficient – specialized equipment is necessary. These advanced systems are priced above the average range but are capable of functioning flawlessly even in temperatures as low as -15 o C. Nevertheless, winter conditions can often be even more extreme, with the temperature dropping even lower and remaining at those levels for extended periods of 2-3 weeks. Mitsubishi Electric offers a solution with their Zubadan series, as does Daikin with their FTXR, FVXG, and FDX models.

By the way! Daikin’s Altherma series heat pumps are the top performers when it comes to operating in extremely cold temperatures. These models can function optimally even at -10 °C and -25 °C. The manufacturer provides extensive operational ranges for both the "air-to-air" and "air-to-water" units. These heat pumps are like the advanced climate control systems found in cars but designed for household use.

Presently, LG is facing competition from Daikin and Mitsubishi in terms of offering new advancements. However, despite the innovative features, this advanced equipment also comes with some drawbacks. These drawbacks include:

• the high cost associated with these systems;
• the ongoing risk of frost formation on the outdoor unit;
• insufficient performance for effectively heating larger apartments or houses.

Tip! To mitigate these issues, manufacturers suggest combining split-systems for heating with alternative heating sources such as solid fuel boilers or other energy-efficient options.

Therefore, contemporary advancements in technology provide the opportunity to utilize climate control devices for heating purposes, with the caveat that the prescribed temperature range specified by the manufacturer is adhered to. Deviating from these guidelines can result in the malfunction of the entire system. Thus, when faced with the requirement for heating or cooling in exceptionally cold conditions, it is imperative to invest in specialized equipment rather than jeopardize the operation of domestic split-systems.

The most popular air conditioners according to buyers’ opinion

On Yandex Market you can find the Mitsubishi Electric MSZ-LN25VG / MUZ-LN25VG split-system.

Split-system Ballu BSVP-07HN1 is also available on Yandex Market.

If you’re looking for a split-system, you might want to check out the Panasonic CS/CU-BE25TKE on Yandex Market.

Another option is the General Climate GC/GU-EAF09HRN1 split-system available on Yandex Market.

Finally, the Ballu BSD-09HN1 split-system is also listed on Yandex Market.