There are a variety of systems for controlled domestic ventilation. These include pure supply or exhaust air systems without heat recovery, as well as supply/exhaust air systems with and without heat recovery. There are also controlled domestic ventilation systems in combination with various heat pump systems.
What classes are there for ventilation units?
Supply air systems
Supply air systems convey outside air to the interior as supply air via fans. The resulting overpressure in the living space, in combination with leaks in the building envelope, ensures increased natural exhaust air.
Z1 – Supply air system, central ventilation unit, without heat recovery
Z2 – Supply air system, single room decentralized, without heat recovery
Exhaust air systems
Exhaust air systems use fans to extract the stale air from the living space to the outside as exhaust air. The resulting negative pressure in the interior, combined with leaks in the building envelope, ensures increased natural supply air.
A1 – Exhaust air system, central ventilation unit, without heat recovery
A2.1 – Exhaust air system, central ventilation unit, without heat exchanger, with exhaust air heat pump for domestic hot water
A2.2 – Exhaust air system, central ventilation unit, without heat exchanger, with exhaust air heat pump for heating water and domestic hot water
A2.3 – Exhaust air system, central ventilation unit, without heat exchanger, with exhaust air heat pump for heating water
A3 – extract air system, single room decentralized, without heat recovery
Central supply/exhaust air systems
Central supply/exhaust air systems are devices installed in separate rooms (e.g. utility room) in combination with air ducts connected to the rooms to be ventilated. These systems provide both mechanically controlled supply and exhaust air. Most units have heat recovery from the exhaust air for the air supplied to the interior. Combinations with heat pumps are also possible.
ZA1 – Supply/extract air system, central ventilation unit, without heat recovery
ZA2 – Supply/extract air system, central ventilation unit, with air/air heat exchanger
ZA3.1 – Supply/extract air system, central ventilation unit, without heat exchanger with air/air heat pump
ZA3.2 – Supply/extract air system, central ventilation unit, without heat exchanger with air/water heat pump for domestic hot water and/or heating water
ZA3.3 – Supply/extract air system, central ventilation unit, without heat exchanger with air/air/water heat pump for air heating and/or domestic hot water and/or heating water
ZA4.1 – Supply/extract air system, central ventilation unit, with heat exchanger and air/air heat pump
ZA4.2 – Supply/extract air system, central ventilation unit, with heat exchanger and air/water heat pump for domestic hot water and/or heating water
ZA4.3 – Supply/extract air system, central ventilation unit, with heat exchanger and air/air/water heat pump for air heating and/or domestic hot water and/or heating water
Decentralized supply/exhaust air systems
In most cases, decentralized supply/exhaust air systems are ventilation units installed in the living space (e.g. in the building envelope) in combination with air ducts or without air ducts for the ventilation of individual rooms. These systems
provide both mechanically controlled supply and extract air. The
majority of units have heat recovery from the exhaust air for
the air supplied to the interior.
ZA5 – Supply/extract air system, single room decentralized, without heat recovery
ZA6 – Supply/extract air system, single room decentralized, with heat recovery
ZA7 – Supply/extract air system, single room decentralized, with heat pump
ZA8 – Supply/extract air system, single room decentralized, with heat recovery, switchover mode