HVAC systems have dramatically changed the way we live. Thanks to their becoming more reliable, efficient and controllable, we are no longer dependent on whimsical weather both for work and for leisure. We have managed to make the environment adapt to our needs.
Nowadays, HVAC climate control has become so dependable and affordable that it has turned into a common necessity in industry and our homes alike. Almost all commercial and public buildings have HVAC systems and the greater part of households have air conditioning.
The more recent the HVAC system, the more sophisticated it is. In most cases, indoor air quality control means controlling fan speed. This is done using a fan speed controller. It regulates fresh air supply or extracts stale air outside the building based on the needs. This can be done manually or on-demand.
In case of manual control, the fan speed can be adjusted via a switch or potentiometer. This can be done locally or remotely.
For automatic fan speed control, i.e. demand-controlled ventilation, an HVAC sensor is connected to the AC fan speed controller or the EC fan.
Numerous combinations are possible, depending on your fan type and ventilation needs. Just select what you need and you will obtain a list of possible solutions to suit your needs and find the best match. 
Local fan speed control offers manual fan speed regulation using a built–in knob.
Remote fan speed control for manual fan speed adjustments is realised using a separate potentiometer or a control switch installed close to the controller or in a separate room. Thus, the requested fan speed is “assigned” to the AC fan speed controller or directly to the EC fan.
Demand-based fan speed control is the most advanced and highly recommended option to control a fan. These solutions optimise indoor air quality and the comfort of the occupants in a discrete way. Significant energy savings can be realised. Fan speed is automatically controlled in function of temperature, humidity, CO2, TVOC, toxic gases or differential pressure. The concept of demand-controlled ventilation revolves around the idea of supplying occupants with an appropriate quantity of fresh air precisely when and where it proves beneficial. Through intelligent airflow management, encompassing demand-controlled ventilation, substantial energy savings are realised during periods of low or zero ventilation requirements, which often constitute more than half of the total time. Conversely, activities contributing to poor indoor air quality necessitate increased ventilation to promptly eliminate the pollutants. The factors influencing air quality are vary temporarily and spatially. In residential buildings, these could be cooking, smoking, painting or even cleaning; in public buildings, they are mainly the release of metabolic compounds and odours, whilst in in parking garages, toxic gas emissions are the top pollutant; in cleanrooms differential pressure is great concern as well.
The most common parameter to base ventilation on is CO2. It has clear advantages especially when occupancy varies widely, for instance in schools, conference rooms, sports halls or shopping centres. The CO2 concentration in such spaces indicates human presence. Of course, your ventilation could be based on temperature and humidity levels or on volatile organic compounds. This depends on the specifics of your application.
Whatever your needs are, we can offer an innovative solution to fulfill them!