What is space heating and cooling with an air-to-air conditioner/heat pump?

An air-to-air heat pump/air conditioner can heat and cool apartments, houses, public places - cafes, offices, shops, etc. 

Air source heat pumps are becoming increasingly popular due to their high energy efficiency, cost and convenience. 

In contrast to electric radiators, oil radiators or other electric heaters, air-to-air air conditioners/heat pumps use much less electricity and are more cost-effective even compared to the cost of solid fuel, gas or, in the case of multi-apartment buildings, central heating.  

The most important thing! Before buying an air source heat pump, you need to assess the suitability of your desired space for the heat pump you choose. The right choice will be determined by both your home and your heating or cooling needs.

The unit consists of an indoor unit that heats or cools the air in the room and an outdoor unit that extracts or, in the case of air conditioning, returns heat to the environment via a compressor.

What can an air source heat pump/conditioner do?

One indoor unit will heat or cool one room and, depending on the selected capacity, also heat the first adjacent rooms if they are separated by a door and kept open. However, the adjacent rooms will warm up a little more slowly and will be only one or two degrees cooler overall.

P.S. In the case of an air-to-air heat pump, the exchange of warm air between rooms will be much better than with radiators.

Ideally, an air source heat pump/air conditioner should be used for open-plan layouts, as is the case today, where the room is combined with the kitchen and corridor, for studio apartments or small apartments/homes where it is possible to keep the doors to adjacent rooms open. 

For larger apartments or houses, if you want to heat or cool the whole house, several monoblocks or a multisplit system with several indoor units and one outdoor unit are installed.

What is space heating and cooling with an air-to-air conditioner/heat pump?
Kasai heat pumps

Is a heat pump/air conditioner suitable as a basic heating method? 

Subject to a number of conditions - YES! However, it is important to take into account the risk factors that the seller will inform you about, such as the maximum outdoor operating temperature for heating and what to do when this temperature exceeds the set temperature for the appliance. 

Before you buy a home heating appliance, consider:

  • Air conditioners with heating function - monoblocks (indoor unit and outdoor unit) mostly operate in heating mode down to -15ºC;
  • Air-source heat pumps with cooling function - monoblocks (indoor unit and outdoor unit) operate in heating mode down to -30ºC and sometimes more;
  • Multisplit air conditioners with heating function (several indoor units and one outdoor unit) mostly operate in heating mode down to -15ºC.

What steps do you need to take before you determine what equipment you need?

Identify your needs!

  • If the basic need will be heating, how basic heating type (no alternative heating source, so you'll use the air source in winter) - Air to air heat pump.
  • Heat only in the shoulder season (a popular choice in spring and autumn when the home is not connected to heating, or in the case of a private home, there is no desire to heat the entire central heating system but to bring a little warm air into the rooms) and in winter you will use another basic type of heating - Air Conditioning with heating function.
  • Other specific requirements - branding, air ionisation, humidification or dehumidification, various smart sensors, automatic restart, fireplace function, sleeping area, etc.

Once you have answered these questions, it becomes clear to the seller what type of equipment to offer, as one equipment will not fit all needs. 

Depending on the needs, an air-to-air air conditioner/heat pump can fulfil different functions, which is why prices can range from a few hundred to a few thousand. Essential! A low air to air heat pump price does not necessarily mean a bad installation. The biggest mistakes can be choosing the wrong heat pump or air conditioner for your daily needs and poor installation. 

What are the next steps once you have defined your needs?

1. If the main function of the room will be inter-seasonal heating - autumn/spring (down to -5ºC on average), then you can safely look at an air conditioner with a heating function that works down to -15ºC or a budget heat pump that works in heating mode down to -30ºC. 

For an air conditioner with a heating function or a budget-range unit, it should be borne in mind that, for the most part, with every degree drop in outdoor temperature, the capacity of the unit to produce heat will drop, because the basic function of an air conditioner is to cool the air, not to heat it, so the heat output at low temperatures is irrelevant. 

On the other hand, for budget heat pumps, even if their outdoor operating temperature is designed for winter conditions of -30ºC, the residual heating power it will produce in winter will be at a falling rate. 

If you don't plan to use the appliance in winter, you definitely don't need to worry about power drops! Up to -5º/-7ºC on average, the equipment produces heat very well. Therefore, for inter-seasonal heating, you can also rely on budget appliances if you have no other special requirements. 

The indicator for the average heating capacity of the appliance is SCOP. How much heat 1kWh of electricity can produce. 

If the equipment is intended for off-season heating, the average can be 4 and up. So 1kW of electricity will produce 4kW of heat.

2. If you use an air source heat pump as your main heating method, it is important to consider the heating capacity of the air source heat pump at low temperatures: -10ºC, -15ºC -20ºC, -25ºC, -30ºC. 

As the air temperature drops, it becomes harder for the air source to produce warm air for the room, but you still need the room to be at your comfort temperature. This is why all appliances that heat below -15ºC are called air source heat pumps, not air conditioners with a heating function.

The manufacturing technology for such plants, in simple terms, involves heating shields, pan heaters in outdoor units, compressor frequencies to enable the plant to produce heat at low air temperatures.  

Make sure that the drop in power at high kW minima is minimal. In fact, units with SCOP close to 5 and upwards are a good solution for basic heating as it will be a relatively economical way of heating even at -20ºC. 

So ask the seller what the kW output of the air source heat pump will be at low temperatures. 

By defining your needs correctly, it is possible to determine which equipment you should choose, whether it is budget equipment that costs less or premium equipment. Just like with clothes - there is no bad weather, but there is the wrong choice of clothes. Not bad weather, but the wrong choice of heat pump.

Another way to use an air source heat pump is to provide additional space heating in winter, in combination with another heating method. You can use this solution to save firewood, pellets, briquettes. Some of the heat will be produced by the heat pump, so you will need to use less solid fuels. You can choose between a budget and a premium heat pump. For example, premium heat pumps have a fireplace function. A room with a fireplace or stove is usually warmer and the temperature is often higher than the set temperature for the heat pump. If the room temperature is different from the set temperature and the fireplace is on fire, the heat pump switches to fan mode to transfer the heat released by the fireplace to other rooms. The air flow decreases as the temperature approaches the initial set temperature.

On the other hand, you can use a budget heat pump in the off-season or at the very beginning of the heating season to save other fuels up to -5º/-7ºC. Imagine that for 4 months of the year you have the opportunity to save on firewood, pellets, briquettes and provide extra comfort. This is a particularly popular option for the elderly, for whom it takes much more time and energy to find and burn firewood.

Similarly, if you go on holiday and are away for a long time, you can set the heat pump to your preferred temperature so the rooms don't cool down when you're away. 

If you want to know more about air conditioners/heat pumps, fill in the application form below and find out: what air conditioners and air source heat pumps we can offer you and what the installation costs are. 

Fill in the application form and we will help you choose the right air-to-air heat pump/air conditioner for you.

Receive offer

Solar panels


  • Harju maakond, Lääne-Harju vald, Lemmaru küla, Väikemõisa-3, 76107
  • Registration no. 16746799
© 2024 KH Energy - All Rights Reserved
Developed quo build

Search product

GDPR Cookie Consent with Real Cookie Banner