THERMOVENT air curtains for service doors and factory gates
FRIGOVENT air curtains for cold store doors and freezer rooms

Saving of costs with THERMOVENT air curtains

Warm air is up to 20% lighter than cold air. It flows through the upper part of the door opening at a speed of about 1m/sec to the outside. Cold air enters at the same time through the lower door area.

At a factory gate (5x5m clear opening) and an outside temperature of 0°C 12.5 m³ warm air per second is flowing outside.

In two minutes, there is a loss of 1,500 m³.

The same amount of cold air 1,500m³ is flowing in at the same time and must be energyintensive reheated.

1 liter of oil is required to heat this cold air from 0° C up to 20° C.



This is the formula for the calculation of the energy required for heating air:

Q = m x c dt
Q = energy MJ
m = mass of air 1,239 Kg/m³
x = airflow m³
c = constant heat of the air 1.005
dt = 20 ° C temperature difference
39 MJ = 1.293 x 1500 X 1.005 X 20
35 MJ = 1 ltr. heating oil




One door opening, described above, costs at an unprotected gate in winter about 1 euro.
- In the summer of 0.5 euro.
With daily 25 door openings, the cost of warm air losses amount to about € 5,000 per year.

80-90% of the hot air leakage can be prevented by the use of THERMOVENT air curtains.