6 FAQs and answers
regarding operation
and service of
ventilation systems

For many residents, having a residential ventilation system is an entirely new experience. Here are six questions, the installer should be ready to answer.

  1. Why are the fans noisy?

    Noise from the fan is typically caused by incorrect installation or balancing of the system. The problems can sometimes be fixed with correct balancing, or if that doesn't work, by installing additional sound dampers in the ducts. The week programs can be timed so that the system operates with a low air change when residents would typically be annoyed and then shifts to a high air change at times when they are typically not. For example, the night mode can be activated to keep the air change at the minimum level during the ‘night period’ set by the residents.

  2. Why is it black around the valves?

    Dust normally whirls around and disappears out of big areas such as windows and doors when you air a room in the traditional way. In a residential ventilation system, however, the dust is concentrated next to the small valves that transport large volumes of air through narrow pipes. The dust can easily be removed using a dry cloth. Don't use a wet cloth, as this will just make the dirt rub off on the wall. Quickly reappearing black marks may indicate that filters need to be changed or that the ducts require cleaning.

  3. Can I vacuum the filters instead of changing them?

    Dantherm always recommends throwing away used filters. This gives a fresher and more hygienic indoor climate, and the extremely fine dust that collects in the filters cannot be removed by vacuuming.

  4. Can I turn off the unit?

    Many new users of residential ventilation systems make the mistake of turning off the unit in order to save electricity and/or heat. The system is designed to run constantly, as otherwise it will start to drag the humid air inside. This increases the risk of bacterial growth developing in the ducts. The advice given to users should therefore be that by letting the system run, they achieve savings on heat that greatly offset the electricity cost.

  5. Why is there a draught around the valves?

    A draught can be caused by incorrect system adjustment. It is therefore important that the installer makes sure that an adjustment form is filled out with a record of how the air in the home is changed, so adjustments can be made on this basis. Draughts can also be reduced by using directional fresh air valves, which can direct the cooler supply air away from areas where residents often sit.

  6. Can my unit function as an air conditioning unit?

    No, a residential ventilation system can only cool using the outside air. There is no cooling function in the system itself. The system replaces the air once every other hour. In comparison, an air conditioning unit circulates the air eight times an hour.


For more information, please download Dantherm’s full Selection Guide for residential ventilation.