VEX: Conditions for capacity data

When measuring capacity data, EXHAUSTO's VEX units are measured with 1 metre of straight duct (2 m for VEX170, VEX270 and VEX280) on all 4 connection spigots.

The uniform low speed profile of the air in the spigot does not cause significant system pressure drop.

This means that bends can be used immediately after the unit.

 Measurement set-up Description 
 Pt Total pressure, i.e. pt1.2 - pt1.1
 Temperature 20°C 
 Density p 1.2 kg/m3
 SFP     Specific power consumption for air transport (J/m3)
 qv Volume flow (l/s)

Absorbed power (Watt) calculated as
SFP x qv x 10-3  or
SFP (J/m3) x qV (l/s) : 1000

 Conversion      1000 l/s = 1 m3/s

”pt” is the total available pressure on both the extract and supply air side, including pressure drop for the M5 filter. Pressure output for VEX100 includes the heating coil.

Pressure drop for heating coil
On VEX200 and VEX300, the pressure drop for the heating coil is  not included, as the heating coil is an accessory located externally in the duct system.

The stated operating curves show the characteristics of the fan with downwards regulation.

The stated SFP curves show the specific electrical consumption in J/m³ air, i.e. the unit's total electrical consumption for both fans, incl. all internal pressure drops.

Calculation programs

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

Go to Calculation Programs
Vex overview

VEX Summary

Get a quick overview of our entire range of compact VEX air handling units with heat recovery.

View the VEX summary here