VEX340H Compact unit

VEX340H Compact unit

VEX340H Compact unit

An air handling unit with counter flow heat exchanger that has a high temperature efficiency and variable adjustable EC motors, which ensures very low energy consumption.

The VEX340H is ideal for residential ventilation, where the air is separated via the ventilation system, removing the risk of odours and humidly being transferred.

The VEX340H size enables it to be transported through a 90 x 200 cm door opening. 

The design is very flexible and the unit can be ordered as a LEFT or RIGHT model.

The unit can also be ordered as an outdoor model. The outdoor unit has a fitted cover that protects it against wind and weather.

Operating conditions

In principle, EXHAUSTO VEX units are designed for use in comfort ventilation - i.e. under ordinary operating conditions.

Where ventilation solutions are required for rooms with high air humidity - e.g. due to humidification, we recommend you make a test calculation with one of our calculation programs. If the calculation shows a risk of condensation after the heat exchanger, an assessment must be made whether the operating conditions can be changed, or whether the unit must be modified to allow condensate to drain off. This is particularly relevant for VEX100CF.

Contact EXHAUSTO for advice on this.

Unique frost protection

Innovative ice detection and control - VEX340H

High-efficiency counter flow heat exchangers can suffer icing, especially if the extracted room air is humid. When the energy from this extracted air is used (when the air cools), the moisture condenses to water vapour, which collects in the heat exchanger.

The high efficiency means that some areas inside the heat exchanger become very cold and in these areas condensed water will freeze and form ice. This can block the air flow.

To ensure EXHAUSTO counter flow heat exchangers can operate in areas that have temperatures below -3 °C EXHAUSTO has developed a return air system. When ice begins to form inside the counter flow heat exchanger, the VEX340H control system circulates up to 30 % of the warmed air back into the cold supply air. This raises the temperature of the outdoor air and the problem of icing is reduced.

Return air principle


Frost protection methods


   NB This function is only active for air regulation methods 2 and 5.


Air regulation – there are seven different air regulation methods:

Airflow control
2. Constant airflow

Constant pressure regulation of extract air
3. Constant pressure-regulated extract air with fixed supply air
5. Constant pressure-regulated extract air with slave-controlled supply air

Constant pressure regulation of supply air
4. Constant pressure-regulated supply air with fixed extract air
6. Constant pressure-regulated supply air with slave-controlled extract air

Constant pressure regulation of both extract air and supply air
7. Constant pressure regulation of both extract air and supply air
8. External control of fan speeds

Capacity curves

Capacity, VEX340H

Below illustrates which capacity ranges individual VEX sizes cover. To calculate the actual capacity data, use our product selection programs.




The compact unit is designed in accordance with German hygiene standard VDI6022, which ensures units are accessible for service and the formation of mould or other bacteria that could negatively impact air quality is prevented. Read more about this standard in the VDI6022 section.



Cabinets are made from Aluzinc® AZ185 class C4 in accordance with EN/ISO12944-2 and insulated with 50 mm mineral wool. This results in low noise emissions to the surrounding environment/installation room.

The panel design minimises the formation of thermal bridges in the unit.


Motor sections


The motor sections are mounted in vibration dampers, which reduces noise in the ducts and eliminates the need to fit flexible connections between the unit and the duct system.

The motor sections can be extracted for easier servicing.

The motors are of type EC and are extremely efficient. They comply with the requirements of the Ecodesign Directive.


Fan impeller


EXstream performance

The units are equipped with EXHAUSTO EXstream impellers, one of the leading air fan impellers on the market in terms of low energy consumption and low sound level.

AHUC - Main board


The easily accessible  connection box with built-in switch disconnector ensures easy access for connecting and adjusting.

Panel filters


Panel filters are easy to replace and can be ordered as Coarse 85% (M5) or ePM1 55% (F7) in acc. with EN779.

Filter size: 716 x 836 x 96 mm.


Mounting base


VEX340 sokkel

VEX340 is delivered as standard with mounting base.




VEX340H Energy-efficient ventilation

The design of the unit has placed particular focus on smooth airflow through the unit in order to achieve the lowest possible pressure loss.

Counter flow heat exchanger 


The VEX340 counter flow heat exchanger is made of aluminium. It is designed to ensure the ratio of heat recovery and pressure loss is at an optimum, i.e.
extremely high temperature efficiency is achieved at low levels of energy consumption.

- Efficiency level without condensation: 80–85 %
- Efficiency with condensation: Up to 94 %
- Weight: 2 x 22 kg

EC motors


The combination of modern EC motors and the EXHAUSTO motor controller delivers extremely low energy consumption and with the EXstream impeller, a high output is achieved.     


Energy labelling

An energy label that states the energy class of the unit in relation to defined operating conditions is available via our product calculation programs.



EXHAUSTO puts great emphasis on providing accurate data. So we use a third party to measure and check our data.

Eurovent certification

All data provided with the VEX100/VEX100CF/VEX200/VEX300 model has been measured.

The units have completed a major test programme in our development department and all of the capacity, efficiency and sound data is collected via testing and in real operating situations.

In accordance with EN1886 and EN13053, Eurovent has tested and certified that EXHAUSTO VEX units meet the following requirements and classes:
Unit’s stiffness:
Air tightness class at -400 Pa:
Air tightness class at +700 Pa:
Filter bypass leakage:
Insulation class:
Thermal bridge class:

L1 (M)
L1 (M)
T2 (M), U1≤1,0
TB3 (M)

This means that a third party has checked that the data that our product calculation program produces complies with the real performance of the unit. Eurovent checks the data by selecting a unit at random and testing that unit at their own facility. If our stated data complies with the Eurovent's test results, we retain our certification. This guarantees the customer that our data is valid.

VDI 6022 - German hygiene standard

EXHAUSTO has designed its units in accordance with the German hygiene standard VDI 6022.

VDI 6022 requirements
The unit's design must make cleaning easy. There may not be areas that cannot physically be cleaned and voids that are inaccessible must be sealed. Plates must be deburred to ensure edges are smooth and corners must be rounded to avoid the risk of injury when cleaning.

In addition,the condensation tray must decline to the outlet, so that water cannot remain in the unit. It is important that the condensation outlet is connected to the drainage system on a horizontal surface.

All non-metallic materials (e.g. seals, filters), are tested to show that they do not promote growth of mould spores and bacteria.

Because the unit is designed in accordance with VDI 6022, it is both more hygienic and easier to clean.


Ecodesign - EU requirements for documentation, energy consumption and labelling of ventilation units.



General information

We have made a compilation of extracts from the Ecodesign guidelines, read more about Ecodesigne here.


Ecodesign data

You will find links to Ecodesign data for the individual VEX sizes under the product name and in the Download section, where we have located Ecodesign data under EU/ECO declarations.


We would point out that the values stated in the declarations have been calculated for a specific operating point.

If a different operating point is desired, we refer to our calculation programs - here you can see whether the desired unit meets the requirements for your operating point and you will find the associated Ecodesign data.

Cooling and heating coils


The following cooling and heating coils are available with the VEX340H:

Water heating coils - HW

Uninsulated external water heating coils. A flexible solution where the heating coil can be fitted where access to warm water is easiest, e.g. the coil can be fitted indoors even if the units is installed outside.

More information about the heating coil is found under Cooling and heating coils.

Electric heating coils - HE 

HCE rundekanaler VEX340 150 100 Uninsulated external electric heating coil. A flexible solution where the heating coil can be fitted where it is most suitable, e.g. the coil can be fitted indoors even if the units is installed outside.

More information about the heating coil is found under Cooling and heating coils.

Cooling coils - CW 

CCW firkantet studs Cooling coil - is available insulated or uninsulated. A flexible solution is to cool ventilation air in those rooms that require it, e.g. south-facing rooms. Frequently, north-facing rooms do not require cooling.

More information about the cooling coil is found under Cooling and heating coils.

SPLIT version

VEX340H is available as a split version.

With some projects, limited space means that internal transport of the air handling unit is difficult or impossible. This is why the VEX340H is available as a split version. It means that the air handling unit can be assembled and tested at the factory as normal – just without sealant. The air handling unit can therefore be easily taken apart at the installation site, transported as single sections, assembled, sealed and commissioned.

The table below shows the dimensions of the largest section (counterflow heat exchanger) and largest cabinet section, so that it can easily be determined whether there is sufficient space to allow internal transport.

Section Dimensions VEX340H
Counterflow heat exchanger Height x length x depth [mm] 755 x 540 x 500
Weight [kg]
Biggest cabinet section Height x width x depth [mm] 1765 x 890 x 290
Motor section Weight [kg]  2 x 17




A wide range of accessories are available with the VEX340

Closing damper - LS

LS runde kanaler 150 100 Closing damper with or without spring-return, for indoor or outdoor fitting.

Outdoor installation 

VEX340OD 150 100

The cabinet is insulated with 50 mm mineral wool.

For outdoor installations, the unit is supplied with a cover that allows cables to be run under the cover on both sides, and at the back of the unit.

We recommend the outdoor unit is fitted with additional support as described in the outdoor instructions.

Water trap

EXHAUSTO also offers a water trap for the unit's condensation drain in dimension DN32.

SIPHONUP (negative pressure) for connection to condensation outlet from the unit.
SIPHONOP (overpressure) for connection to any cooling coil in the supply air duct.

SIPHONHE02 (accessory) hot-wire is used to keep the water trap and water pipe free of ice. A thermostat is fitted to the hot wire to ensure low energy consumption.

Add all about the product series VEX340H Compact unit


Get free advice on ventilation products and system solutions

Export Requests:
Odensevej 76
DK 5550 Langeskov

Tel +45 6566 1236

Calculation programs

Use EXHAUSTO's free calculation programs for calculating ventilation plant and system solutions

Go to Calculation Programs
Teaser ecodesign

Ecodesign Directive

EXHAUSTO VEX air handling units and fans comply with the Ecodesign Directive. Read more here.

See more about Ecodesign here