Central heat recovery ventilation units

Central heat recovery ventilation units: whole-house heat recovery ventilation for a house or larger apartment

A central heat recovery ventilation unit is a ventilation device with heat recovery that provides controlled residential ventilation and heat recovery from exhaust air. It is intended for buildings where a duct system can be installed: fresh air is supplied to living areas, while stale air is extracted from the kitchen, bathroom and utility room.

This category includes central ventilation units in different sizes, from smaller solutions for apartments to larger units for houses. If you are also comparing other types of heat recovery ventilation, see the overview of heat recovery ventilation units. The technical data for each product are listed in the "Product Details" tab on the product page.

How a central MVHR unit works

Central ventilation works through a duct distribution system. The unit simultaneously supplies fresh air and extracts stale air, while transferring heat from the exhaust air to the supply air. Heat recovery ventilation therefore does not only mean air replacement, but also a reduction in heat losses that would occur with conventional airing by opening windows.

Heat recovery and controlled ventilation

Fresh air is usually supplied to living rooms, bedrooms and other living areas, while stale air is extracted from rooms with more moisture or loads, such as the kitchen, bathroom and utility room. This enables continuous air exchange without uncontrolled draughts. For heating, this means that part of the heat that would otherwise leave the building is returned to the supply air. For the room, it means a more organised air exchange throughout the entire building.

Counterflow and enthalpy exchanger

Counterflow plate heat exchanger

Most units use a counterflow plate heat exchanger made of polystyrene. In it, the fresh and stale air streams do not mix, while heat is transferred through the exchanger surfaces from the extract air to the supply air. In individual versions, the heat recovery efficiency reaches up to 98%, depending on the size and design of the unit.

Enthalpy exchanger

One version uses an enthalpy exchanger, which transfers moisture as well as heat. This is an important difference, as this type of exchanger does not deal only with air temperature, but also with part of the moisture that returns between the two air streams.

Which central heat recovery ventilation unit to choose

The choice depends mainly on the size of the building, planned airflow, mounting method and duct diameter. The range includes units with airflows from 100 m³/h to 720 m³/h, with efficiencies from 76% to 98%. When comparing, also check the power, noise, connections, filters and control method.

Small unit for an apartment

For a smaller apartment, a small ceiling unit for an apartment with airflow up to 100 m³/h is suitable. It has a heat recovery efficiency of 76%, power of 56 W, is intended for ceiling or suspended mounting and includes a remote control. For slightly greater requirements, units with airflow of approximately 130 to 331 m³/h are available, with efficiency from 83 to 94% and power from 45 to 182 W. Among them is also a compact unit with airflow of 181 m³/h, which has power of 53 W.

Unit for a medium-sized house

Units with airflow from 300 to 450 m³/h are intended for a medium-sized house. They have efficiency from 90 to 98%, EC motors, automatic bypass, G4 and F7 filters and 125 or 160 mm connections. An example of this version is a floor-standing unit with airflow of 390 m³/h, with efficiency of 95% and power of 180 W. If you need reheating of the supply air, there is also a unit with an integrated electric reheater with power of 1500 W, airflow of 340 m³/h, efficiency of 90%, four 160 mm connections, a counterflow heat exchanger, EC motors and automatic bypass.

Unit for a large house

For larger houses, a heat recovery ventilation unit for a house with higher airflow is suitable. The range includes a larger unit with airflow up to 720 m³/h, with efficiency of 93% and a 200 mm connection. This choice makes sense where a larger duct distribution system and a larger volume of exchanged air are planned.

Equipment and control

EC motors, filters and bypass

A common feature of central heat recovery ventilation units is low-consumption EC motors. The supply and extract sides are equipped with filters, most often G4, with F7 also available as an option. Most units have an integrated automatic bypass, which enables operation around the exchanger when appropriate. Noise depends on the size and design of the unit and ranges from 24 to 41 dB(A) at 3 m.

Control via panel or app

Airflow and speed are adjustable on selected units. Control can be via a control panel or an app, depending on the individual model. When choosing, check which control method suits you and whether you want a basic manual setting or control via an app.

Installation and connections

Ducts and connections

A central heat recovery ventilation unit is connected to round ducts with diameters from 100 to 200 mm, most often 125 and 160 mm. Mounting can be suspended, for example under the ceiling, in a technical room or in the attic, or floor-standing or wall-mounted, depending on the version. Duct installation and condensate drainage are required during installation. For air distribution, round ducts and insulated pipes are available in a separate category.

Maintenance and filters

Regular checking of the filters on the supply and extract sides is important for correct operation. Dirty filters restrict airflow and can affect the operation of the unit. For each product, check the prescribed filters and technical data, while suitable replacements can be found among replacement filters for heat recovery ventilation units.

Frequently asked questions about central heat recovery ventilation units

When should you choose a central heat recovery ventilation unit and when a single-room heat recovery unit?

Choose a central heat recovery ventilation unit when you can install duct distribution throughout the building and want to ventilate several rooms at the same time. A single-room heat recovery unit is more suitable for an individual room or where a duct system cannot be installed sensibly.

What airflow does a heat recovery ventilation unit for a house need?

Airflow depends on the size of the building and the ventilation design. This category includes units from smaller versions up to 100 m³/h, medium versions up to approximately 450 m³/h and larger units up to 720 m³/h. For an exact choice, check the Product Details of each unit.

Does a central heat recovery ventilation unit need condensate drainage?

Yes, condensate drainage must be planned during installation. This is part of the correct installation of a central ventilation unit with heat recovery, along with duct routing and suitable connections.

What does a heat recovery ventilation unit with EC motors mean?

A heat recovery ventilation unit with EC motors uses low-consumption motors. These motors are a common feature of the units in this category and are important for continuous operation of controlled ventilation.