How to choose the right heat recovery ventilator for your home?

The number of heat recovery units available on the market is very large. They differ according to many criteria - for example, there are both centralised ventilation units with heat recovery and decentralised ventilation + heat recovery units. This is what we will be talking about. If you don't know what heat recovery is, you can read more about it in "Heat recovery ensures full indoor air exchange and helps save heat".

Kā izvēlēties savam mājoklim piemērotu rekuperācijas iekārtu?


These units differ in their design, capacity and other characteristics. The main conditions for selecting a heat recovery unit are the volume (cubic capacity) of the room and the number of persons in it. There are also other factors that often need to be taken into account, so it is best to consult a specialist before purchasing a specific unit. specialists offer free telephone consultations and site inspections can also be arranged.

Adequate fresh air supply

The main purpose of any ventilation is to ensure that there is sufficient air exchange in the room to ensure that there is a constant supply of fresh air and that there is no increased levels of carbon dioxide (CO2), which can lead to health problems.

The main factors for selection are the area, cubic capacity and number of people in the room. Based on these criteria, calculations are made to select the appropriate room ventilation unit with the most appropriate supply/exhaust cubic capacity. The adequacy of the capacity or power of the equipment for a given space is the most important condition for selection.

Different types of decentralised ventilation can be chosen

There are several types of decentralised ventilation and heat recovery systems available on the Latvian market today, differing in their design.

Ducted decentralised ventilation equipment

First of all, ducted decentralised ventilation systems. This type of unit is built into a duct, where two separate ducts supply and exhaust air simultaneously, the air passing through a heat recovery unit on the way, where the heat of the exhaust air is extracted and transferred to the incoming air.

The air streams flowing in opposite directions do not come into contact with each other, but transfer heat from one to the other through a heat exchanger of a high thermal conductivity material (copper, aluminium, etc.). A single hole drilled in the external wall of the building is sufficient for the installation of such a system.

"The main factors are the size, cubic capacity and number of people."

Impulse devices

The other type is the so-called pulse unit, in which the incoming and outgoing air flow in two separate tubes and a ceramic or other material heat accumulator is used for heat exchange. The unit itself operates for a while in exhaust mode, storing the heat of the outgoing air, before switching to supply air, returning the heat previously stored to the incoming air.

However, this type of installation will require two holes to be drilled in the wall. They also have an electronic control unit, which complicates installation and increases costs.

Type 3 - room heat recovery unit in a separate module

There is also a third type of heat recovery unit, where the heat recovery unit is not placed in a pipe, but in a separate module in the room, similar in size and appearance to an air conditioner. The main difference between this type of equipment and ducted heat recovery is that it does not require a minimum wall thickness in order to fit harmoniously into the building structure.

In particular, the heat recovery unit is not built into a pipe of a certain length, but is located in the room itself, allowing it to be installed in buildings with walls only 10 cm thick. This is mainly for design reasons, so that in buildings with thin walls, the end of the pipe does not protrude inside the room or outside the house and spoil the overall design. Such installations may require one or two boreholes in the external wall of the building.

Experts will help you choose

It is also important to choose the right place in the room where to install these devices (all types). The main condition is that they are installed in the external walls of the building, not in the partitions, as this will have no effect. Indoors, the equipment is usually installed about 30 cm from the ceiling, but it is also important to find the best place in the room to install the equipment. This is chosen on a case-by-case basis to find the best and most efficient location.

People without prior knowledge in this field can often have difficulties with making the necessary calculations to choose the right equipment and the optimal solution, which is why's specialists offer assistance in choosing different equipment and installation locations.

All questions can be addressed to the contact phone +371 2564 2178, by e-mail or simply by filling in the application form on the company's website The company's staff will contact you and provide free telephone advice on any questions you may have. The free service also applies to site inspections in Riga and the immediate vicinity, and outside the region - by arrangement.