Residential ERV/HRV is whole house ventilation with heat recovery. You can also call it whole house air exchanger or whole house fresh air system.
Constant fresh air in your home is an important aspect to maintain the indoor air quality. A good ventilation system will protect your family from unpleasant odors and harmful contaminants such as formaldehyde and VOCs. Opening window is a simply way to increase ventilation, it can make your air feel less stuffy, but pollen and other allergens will be invited into your home at the same time.
The delta tone used in Sinus Congestion is meant to vibrate at a particular frequency that will help lessen your pain and clear your sinuses. Combined with your medications, healthy eating, eating plenty of fruit (particularly those rich in Vit.C) and water consumption, you will get the sinus congestion relief that you terribly need.