Modern split systems and mobile units are capable of not only cooling the air, but also heating it. It is important to understand: is it possible to use air conditioning for heating in winter or is the equipment not designed to work in thermal mode at low temperatures outside.
Features and principle of operation of a split system for heat
Any split system is not a heating device, there is no heating element in it, so there will be little climate control system to maintain quality at a comfortable temperature. This is due to the features of the principles of its functioning.The air conditioner is in heating mode only at certain outdoor thermometer values.
Most splits can give out warm air. In general terms, this process can be called the reversal of freon, in which the compressor is responsible for its pumping towards the room: heat is taken from the outside and carried inside. To change the refrigerant stroke, a four-way valve is required, which swaps the evaporator and condenser. In the indoor unit, condensation of freon occurs with the release of heat, and in the external unit - evaporation, in which the air conditioner absorbs heat. Heat is pumped from one place to another, but is not generated. Because of this, in the heating mode, the efficiency of the air conditioner is greatly reduced, which makes its operation ineffective at street temperature closer to zero marks.
The heat exchanger of the outdoor unit becomes infinitely small: when the thermometer is closer to zero and below its area is not enough to remove the cold.
Outside temperature limits
Most air conditioners with heating function have certain limitations: manufacturers produce climate control equipment with the programmed ability to work on heat at a minimum outside temperature of -5 ° C. In practice, it has been proven: with minus indicators, the split system should not be started. We can conclude that it is impossible to use the air conditioner for heating in winter. In the best case, bask in this way will turn out until November.
Failure to comply with the recommendations given in the instructions and during installation leads to wear and tear in the constant start-stop mode. For modern two-component devices, there is a special program in which a signal is sent from the temperature sensor to the board about the inadmissible temperature values of the heat exchanger, and the device is turned on. In extreme cases, only a fan will work, or one of the error codes will be displayed - each brand has its own codes.
How to turn on and set the air conditioner to warm air
If the outdoor temperature is observed, turn on the air conditioner using the ON button on the remote control or on the external panel.
Find the HEAT or MODE button and then the icon with the image of the sun, drop, snow or fan. If there is nothing like this, then this model of air conditioner is not designed to heat the room.
After switching the system to thermal mode, use the “+” and “-” buttons to set the desired temperature. It should be higher than the room temperature.
After setting the desired temperature, the fan will turn on, and then warm air will begin to flow. The set climate will be established within 10 minutes.
There are models in which you first need to set the mode and temperature, and then press the ON button. Detailed instructions are provided with the device upon purchase.
Problems and risks of operation
If you turn on the air conditioner for heating when the outside temperature is below the permissible level, the following problems may occur:
- system performance will decrease significantly;
- the capacitor of the outdoor unit will freeze;
- the fan of the outdoor unit will break;
- the oil thickens, as a result of which the compressor will break down during system startup.
Efficiency and thermal efficiency of air conditioners
Efficiency of an air conditioner is understood as an assessment of the system performance. The calculation of this value is made from the ratio of consumed and useful power. In this case, net power is the amount of reduced heat per unit time. You can talk about effective work when the efficiency of the air conditioner in heating mode is more than 1.
Usually at positive temperatures in the street the amount of heat generated exceeds the amount of energy consumed by 2-4 times. If the power consumption was 1 kW, then the heating power will be approximately 2-4 kW. The manufacturer indicates the rated power consumption, which may slightly differ from the actual values.
The energy efficiency factor of an air conditioner is usually labeled C.O.P. (Coefficient of Performance). It can be calculated by correlating two values - heating power to power consumption.
If the thermal power is 3.5 kW, and the consumption is 1.2 kW, then the efficiency will be approximately 2.9 kW. This is considered a fairly large performance. If the temperature outside decreases, respectively, the energy consumption increases, while the coefficient drops markedly. A ratio of less than 2.4 is considered low. Instruments with these values are labeled below the A-class.
Winter kit
There are two myths about efficient air conditioning in winter cold.
The first myth: when installing the winter kit on an air conditioner with a heating function, it can be used at low temperatures. There is some truth in this - turning on the device in this case is allowed, but not to heat, but to cold.
The standard winter kit consists of three elements:
- fan slowdown device;
- compressor crankcase heating;
- drainage heating - a self-regulating heating element.
When the air conditioner operates for heating in winter, there is no need to slow down the fan, on the contrary, it should rotate even more. Therefore, such a complete set of split will help only when cooling the room, when it is necessary to slow down the rotation of the fan to maintain the condensation temperature.
Installation of a winter kit for inverters is in most cases not completely, but partially, since many devices have a fan retarder built into a complex electronics system.
The second myth: the purchase of a modern air conditioner with a built-in winter kit and an anti-icing program will allow it to function for heating to the indicated temperature parameters, which very often reach serious values. This is not entirely true. Only units of models belonging to the semi-industrial series will be able to warm the room. In addition to the built-in drain pan heater, they have a larger heat exchanger. Such models provide decent heating efficiency in winter with air conditioning even at -25 ° C. The rest will be able to work qualitatively with such external parameters only for cooling.
The main manufacturers and series of devices with the programmed ability to heat the premises in cold weather:
| Manufacturer | Series | Permissible temperature |
| DAIKIN | CTXG-J / MXS-E | -15 ° C |
| Toshiba | DAISEKAI SKVR | -15 ° C |
| Hitachi | PREMIUM, ECO | -20 ° C |
| Panasonic | HE-MKD | -15 ° C |
| MITSUBISHI ELECTRIC | DELUXE, PKA-PR (not all models) | -15 ° C |
In modern conditions for the production of HVAC equipment, it is possible to use air conditioning for heating, but the purchase of an all-weather split will be much more expensive.
Mobile air conditioning as a winter heater
Mobile air conditioning combined in one case all the internal working elements of the chiller. When working in the cold, the air intake goes from the room, inside it is divided into two parts: the cooled stream goes back, and the warm one is removed through the outlet corrugated sleeve.
To heat the air in most monoblocks, a heater is installed - a built-in electric heater. The compressor works the other way around: cold air enters the pipe, and hot air enters the room. At the same time, electricity consumption increases significantly. Accordingly, the efficiency decreases, and heating with a mobile air conditioner becomes expensive.
At the same time, there are three significant advantages:
- with the help of this design it is possible to serve areas of up to 60 m²;
- air conditioning heating in winter is possible at any temperature outside, since there is no external unit at all;
- Ceramic heating elements for heating air can be installed in the mobile unit.
An accurate thermostat is placed in a monoblock with heating mode, which, when the device reaches the set temperature, will turn off the compressor.
There are not many manufacturers producing high-quality monoblocks with a heating function. The most famous among them:
| Manufacturer | Models |
| Ballu | BPAM-07H |
| BORK | Y502 |
| DANTEX | RK-09PSM-R |
| Rolsen | RAP-09CWAD |
| TIMBERK | AC TIM 07H P3 |
Choosing an air conditioner with heating function
Regardless of the preferred design of the device, when choosing an air conditioner for heating, you must pay attention to the following characteristics:
- rated power consumption;
- heat performance;
- energy efficiency class;
- Operating temperature range by heat;
- the presence of the automatic defrost function of the external unit.
There are several other factors that influence the choice of an air conditioner for heating:
- room area and ceiling height;
- targeted use of the premises.
It is better to give preference to inverter premium split models with a built-in winter kit and an enlarged heat exchanger, since they are characterized by reduced electricity consumption, increased heat production capacity and a favorable efficiency coefficient.
