VEX300T

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.

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

VEX300T is equipped with an optimised centrifugal impeller with backward curved blades.

The wheel is made from a composite material and its shape provides great performance with low energy consumption.

The VEX300T range is supplied with an integral heating coil or cooling-heating coil

HE: Electric heating coil (requires airflow control, accessory - AFC)

HW: Water heating coil

CW: Cooling-heating coil (option for cooling in summer and heating in winter)

DX: Cooling-heating coil (option for cooling in summer and heating in winter)

See more about cooling/heating coils under the technical data for the size in question.

Note: It is also possible to order the VEX300T without cooling and/or heating coils

The easily accessible connection box with built-in isolator switch and control fuses ensures easy access for connection and adjustment. Read more about electrical connection in the guide “Electrical guide for VEX310-350T”

Panel filters for supply air and extract air– the filters are easy to replace.

The filters are available in the following filter classes: ePM1 80% (F9), ePM1 55% (F7), ePM10 65% (M5) and Coarse 65% (G4).

See filter size under technical data for the individual VEX size.

With some projects, limited space means that internal transport of the air handling unit is difficult or impossible. This is why the VEX300T 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.

It is possible to insert a 48-mm filter ahead of the standard filter on the supply air side. Placing a coarser filter in front of a finer filter reduces soiling on the finer filter. Depending on the outdoor air and the desired quality of the supply air, this can be a good idea/option.

The filters for pre-filtration are available in the following filter classes: ePM1 55% (F7), ePM10 65% (M5) and Coarse 65% (G4).

Pressure drop, etc. can be calculated in the product selection programme EXselectPRO.

The VEX300T is designed with de-icing bypass. If there is a risk of icing, then a certain amount of outdoor air will bypass the heat exchanger and go directly to the after heating coil. This increases the demands on the heating coil’s output. However, it avoids a costly preheating coil. The drawing below is an example of a de-icing situation, where 20% of outdoor air is directed through the bypass damper.

Heating coil and de-icing function:

The de-icing situation is shown above, a heating coil is included here. This is completely necessary, in order for the de-icing function to function correctly. Without the heating coil, the de-icing process will cause the temperature of the supply air to fall and sooner or later the VEX unit will stop because of icing.

The heat exchanger has two forms of frost protection: temperature-controlled or pressure-controlled. The actual de-icing can take place in several ways, depending on whether an after heating coil has been fitted. A post-heat surface is always recommended to maintain continuous ventilation.

The control system has temperature-controlled frost protection as standard. It is an inexpensive solution and provides sufficient frost-protection in some situations.

A temperature sensor is fitted inside the heat exchanger and if the temperature falls to a pre-set value, de-icing begins. This temperature level is factory set to 0 °C but it can also be changed to a new value via the control system.

Temperature-controlled frost protection triggers the de-icing process even if there is no ice in the heat exchanger.

The control system monitors the actual airflow and also the pressure drop across the heat exchanger. If ice forms in the heat exchanger, the pressure drop across the heat exchanger will increase and when it exceeds a pre-set value, de-icing begins.

Pressure-controlled frost protection only starts de-icing when ice has actually formed, regardless of whether there are sub-zero temperatures.