LLB-Serie - aktive Lüftungsgeräte mit Warmwasserbereitung | © alpha innotec

Area of application: single-family house

Would you like to ventilate your house fully automatically and efficiently while relieving the load on the heating system and at the same time preparing hot water? Then a device from the LLB series is the right choice for you. The central air-to-air heat pump combination units with countercurrent heat exchanger ensure fresh, pleasantly tempered air in your house all year round.

A ventilation system with heat recovery increases the air quality in your house, counteracts mould growth and reduces heating costs. Thus a device of the LLB series has a positive effect on your health as well as on the building fabric and your wallet.

Why a ventilation system?

A ventilation system has many advantages that make it a sensible purchase: The house is optimally ventilated throughout, much better than would be possible with manual window ventilation. This increases the air quality in the house, increases the concentration of oxygen and, thanks to modern filter technology, also reduces pollution. The latter is particularly valuable for allergy sufferers because the concentration of pollen in the air can also be massively reduced in this way. You and your home will benefit from controlled ventilation of your living space: if there is more oxygen in the air, it makes us fitter, more alert and more efficient overall; at the same time, continuous air exchange prevents the formation of mould.


About the LLB-Series

With the LLB series from alpha innotec, everything needed for comfortable living is accommodated in one device: ventilation, temperature control and domestic hot water preparation. By using the thermal energy in the exhaust air, the drinking water is heated - so heat is not lost during ventilation, but is available as warm shower water, for example, or can be used to heat the supply air.

Flexible with compact dimensions: The system is ideally suited for the integration of existing solar thermal or wood boiler systems for domestic hot water preparation and, despite its integrated 185 litre storage tank, requires only a small footprint. Thermal disinfection is also possible via an integrated electric heating rod.

Advantages for the homeowner

  • Ventilation, heating support and domestic hot water preparation in one system
  • Passive house certified (LLB 317)
  • Energy-efficient ventilation with heat recovery
  • Low space requirement due to compact design
  • Uniformly high air quality
  • Preventive against mould formation

Advantages for the installer

  • Low installation costs
  • Easy maintenance
  • Domestic hot water temperature up to +55 °C
  • Flexible combination with e.g. solar thermal systems
  • High performance due to high conveying capacity

Application: Fresh air and domestic hot water for single-family houses

The ventilation units of the LLB series are able to supply buildings up to a living area of 170 m² with tempered fresh air and hot water. They are therefore ideally suited for use in single-family homes.

Technical details

The ventilation systems of the LLB series are characterised by the following features. Further technical details and downloads for the individual units can be found on the respective product page.

  • Countercurrent heat exchanger for controlled heat recovery
  • Heat recovery rates of up to 80 %
  • Additional air heating by means of heat pump
  • Alternating and with priority circuit for drinking water preparation by means of heat pump via exhaust air
  • Equipped with all safety devices
  • Filled with fluorinated greenhouse gas (R 134a)
  • Powder-coated outside (RAL 9006 white aluminium)
  • Double-walled housing made of fvz sheet metal (inside) with 30 mm insulation

All ventilation units of the LLB-Series

The two units of the LLB series are largely identical; the difference lies in the enthalpy heat exchanger, with which only the model LLB 317 BE is equipped. This ensures particularly efficient and hygienic moisture recovery and is protected against freezing.

LLB 317 BMaximum air output 370 m³/h at 100 Pa, suitable for living spaces up to 170 m²; with automatic bypass
LLB 317 BEMaximum air output 370 m³/h at 100 Pa, suitable for living spaces up to 170 m²; with automatic bypass and enthalpy heat exchanger

Prices - overview

How much a ventilation system costs to purchase depends on various factors, e.g. the type of system, the number of people in the household, the size of the building, etc. The cost of a ventilation system depends on the type of system, the size of the building, etc. The cost of a ventilation system depends on the type of system and the size of the building. In principle, the costs for a central ventilation system (incl. installation) start at around €8,000.

Installation in a new building is usually a bit cheaper because it involves less effort - although it is generally quite expensive because air ducts have to be built. Since this can easily take several days, installation costs of around €1,000 to €3,000 are to be expected with central ventilation.

Alternatives to the LLB-Series

The unique selling point of the LLB series is the integrated water heating. If you do not need it, alpha innotec offers you various other ventilation systems; both centralised and decentralised, with active or passive heat recovery.

SeriesConstructionSpecial features
LG-SeriesCentral ventilationPassive heat recovery
LD-SeriesDecentralised ventilationPassive heat recovery, almost invisible


The LG series units are also used for central ventilation, but are equipped with passive heat recovery. Thanks to particularly efficient heat exchangers, they can recover a great deal of heat (up to 96%) without having to use too much energy.


Those who prefer a decentralised ventilation system will find what they are looking for in the LD series. The units have passive heat recovery, are particularly easy to install and require hardly any planning. This makes them not only suitable for use in new buildings, but also particularly easy to retrofit in old buildings.