Just a few years ago, air conditioning was associated mainly with cooling indoor spaces during summer. Today, modern wall-mounted air conditioners are increasingly being used as efficient heating solutions. As a result, many homeowners are asking a simple question: can an air conditioner heat a home throughout the winter, and is it cost-effective?
The answer is yes.
An air conditioner equipped with a heating function operates as an air-to-air heat pump, extracting thermal energy from the outdoor air and transferring it indoors. This makes air conditioning a highly efficient heating solution. Especially during transitional seasons and milder winter conditions.
Modern units such as HEIKO MORA have been designed for year-round operation. Importantly, they come equipped with a bottom heater as standard, ensuring stable performance even at low outdoor temperatures. Thanks to this feature, air conditioning can serve not only as supplementary heating source but, in many cases, as the primary heating system for a building.
How Does The Heating Function in an Air Conditioner Work?
The operating principle of an air conditioner in heating mode is very similar to that of a heat pump.
The system extracts thermal energy from the outdoor air and transfers it indoors. As a result, it uses significantly less electricity than conventional electric heaters to produce the same amount of heat.
In practical terms, this means that users recive more thermal energy than the electrical energy consumed by the unit. This is why heating air conditioners have become one of the most popular solutions for heating apartments, single-family homes, offices and commercial spaces.
In addition, modern systems offer rapid temperature adjustment, precise control, and reliable year-round operation.
Can Air Conditioning Be the Main Heating Source?
This is one of the most frequently searched questions among homeowners considering an air conditioning system.
In many ceses, the answer is yes. However the suitability of air conditioning as the primary heat source depends on several factors, including building insulation, heat demand, and local climate conditions.
In well-insulated homes and apartments, air conditioning can effectively provide heating for a significant part of the heating season. It performs particulary well during spring and autumn when traditional heating systems often operate less efficiently.
Increasingly, air conditioners are also being used alongside heat pumps or other heating systems. This approach improves flexivility and allows users to optimize operating costs throughout the year.
How Low Can Outdoor Temperatures Go While Maintaining Heating Performance?
One of the most important factors when selecting an air conditioner for heating is its operating range in winter.
The HEIKO MORA air conditioner can operate in heating mode at outdoor temperatures as low as -20°C. This allows the unit to provide efficient heating not only during spring and autumn but also throughout typical winter conditions experienced across Europe.
This is a significant advantage compared to many entry-level air conditioners designed primarily for cooling applications.
For users, this means greater independence and the ability to relay on air conditioning as a heating source for much of the year.
Why Is a Bottom Heater Essential in Winter?
When operating in heating mode, the outdoor unit periodically enters a defrost cycle. During this process, condensation forms and may freeze at low temperatures.
For this reason, a bottom heater is one of the most important features of an air conditioner intended for winter operation.
In the HEIKO MORA unit, the bottom heater is included as standard equipment. Its purpose is to prevent condensate from freezing and to maintain reliable outdoor unit operation during cold weather.
As a result, the system continues to opetate safely and efficiently even when temperatures fall well below freezing.
For users, this translates into greater reliability and improved operational safety throughout the heating season.
HEIKO MORA – Designed for Year-Round Comfort
As part of its 2026 product portfolio expansion, HEIKO introduced the MORA wall-mounted air conditioner, developed for users seeking both efficient cooling and reliable heating performance.
The unit incorporates a range of features designed to improve comfort and indoor air quality. Particulary noteworthy are the SELF CLEAN and 56°C Steri Clean technologies, which help keep the heat exchanger clean and hygienic.
In addition, MORA includes the I FEEL function for more accurate temperature control based on the user’s location, as well as built-in Wi-Fi connectivity for convenient remote operation via a mobile application.
By combining cooling, heating and advanced comfort-enhancing technologies, MORA is an attractive solution for both new construction projects and renovation applications.
Is Heating with Air Conditioning Cost-Effective?
In many situations, absolutely.
A modern air conditioner with a heating function can provide an efficient and economical heat source during transitional seasons and typical winter conditions. Moreover, investing in a single system allows users to enjoy both cooling and heating throughout the year.
The key factor is choosing the right model. If air conditioning is expected to serve as a heating solution during winter, it is important to select a unit designed for low-temperature operation and equipped with features that enhance reliability and performance.
HEIKO MORA is a good example of a system that meets these requirements. As a result, it can serve as an attractive alternative or complement to traditional heating solutions in residential and light commercial buildings.