Cooling for halls and commercial premises: efficient, mobile, without refrigerants

The challenge

In many companies the summer problem is underestimated until the first hot days arrive. Machine waste heat, solar radiation on the roof and large hall volumes without active cooling quickly lead to temperatures at which concentrated work is hardly possible. Conventional air conditioning is not a realistic answer for halls of this size: it is expensive to buy and run, requires an outdoor unit, refrigerant lines and a fixed installation, and simply reaches its limits above a certain hall size.

Adiabatic evaporative cooling is the technically and economically superior approach for commercial applications. We explain how the principle works, where its strengths lie and where the decisive differences in equipment quality are.

How adiabatic cooling works

The principle: physics instead of compressor technology

Evaporative cooling uses one of the most fundamental physical processes: when water evaporates, it extracts energy from the surrounding air and cools it down. This is exactly the principle behind every adiabatic air cooler, and it is the same effect that makes a summer day feel more pleasant after a rain shower than on a dry, hot day.

Inside the unit, warm outside air is drawn in and passed through water-soaked cooling pads. The water evaporates, the air cools down and is released into the room slightly humidified. There are no compressors, no refrigerants and no outdoor unit. All the unit needs is a power supply and a water supply, either via the integrated tank or a fixed water connection.

The achievable temperature reduction depends on several factors: the initial temperature, the relative humidity, the air exchange in the hall and the ratio between unit capacity and room volume. Reductions of up to 10 °C are readily achievable.

Possible temperature reduction, shown as outlet air temperature in °C depending on intake air temperature and relative humidity:

Intake air	20 % RH	25 % RH	30 % RH	40 % RH	50 % RH
30 °C	17.2 °C	18.2 °C	19.2 °C	21.1 °C	22.8 °C
32 °C	18.5 °C	19.6 °C	20.7 °C	22.7 °C	24.5 °C
34 °C	19.8 °C	21.0 °C	22.1 °C	24.3 °C	26.2 °C
36 °C	21.2 °C	22.4 °C	23.6 °C	25.9 °C	27.9 °C
38 °C	22.5 °C	23.9 °C	25.1 °C	27.5 °C	29.5 °C
40 °C	23.8 °C	25.3 °C	26.6 °C	29.1 °C	31.3 °C
42 °C	25.2 °C	26.7 °C	28.1 °C	30.7 °C	33.0 °C
44 °C	26.5 °C	28.1 °C	29.6 °C	32.3 °C	34.7 °C

Example: at 36 °C and 30 % relative humidity, the cooler blows out air at approx. 23.6 °C, around 12 °C cooler.

Humidity rises only moderately, typically by 2 to 5 percentage points. With good ventilation in the hall, this increase is not noticeable: the relative humidity is no higher than it is in the hall at night anyway.

Unique feature: the pre-filter

What sets our units apart: the integrated pre-filter

In practice, one decisive factor is often overlooked: the quality of the air entering the cooler. In commercial halls the air carries dust, chips, pollen, fibres or abrasion particles, in considerable quantities depending on the industry. Without pre-filtering, this material settles in the cooling pads, reduces the cooling capacity, increases the cleaning effort and considerably shortens the service life of the pads.

Our models from the OKM12EC upwards are equipped with an integrated G4 pre-filter system that cleans the intake air before it reaches the cooling pads. It sounds like a detail, but in practice it makes the difference between a unit that runs reliably for years and one that loses performance after one season. Especially in dusty environments such as woodworking, metalworking, logistics or food production, this difference is immediately noticeable in performance, hygiene and operating costs.

The pre-filter is designed for easy maintenance and can be removed and cleaned without tools. Anyone comparing our units with competing products will notice that pre-filters of this kind are not a matter of course. They are a deliberate quality feature that we consider indispensable for continuous commercial operation.