Controlled Ventilation Specified by Code
Fresh Air Ventilation Prodcuts Compliant with ASHRAE Standard 62.2.
New energy efficiency requirements have tightened homes to the point that fresh air ventilation cannot be assumed. It must be managed. HVAC engineers have developed ASHRAE Standard 62.2 specifying the minimum air changes needed in any given residence. In most states, fresh air ventilation is required to meet building codes for new construction or to obtain energy tax credits.
What are the different types of ventilation systems? Home ventilation system types include variations of balanced ventilation, supply ventilation, or exhaust ventilation.
Balanced Ventilation Systems
Heat Recovery Ventilator (HRV) and Energy Recovery Ventilator (ERV)
- Uses a fan to supply air into the home while simultaneously exhausting an equivalent amount of air out of the home
- Operates continuously or intermittently
- Ducted into the central air distribution system
- Independent supply and return air duct system into one or more areas
Supply or Central Fan Integrated Ventilation (CFIV) Ventilation Systems
Intelligent, calibrated fresh air supply (FAS)
- Utilizes the central fan to supply outdoor air through a controlled duct
- Piggy-backs central fan operation during heating and cooling to maximize efficiency
- Operates intermittently
- Circulates fresh air within the entire home
- Automatic fresh air damper (FAD) prevents infiltration during off periods
Exhaust Ventilation Systems
Bath fans, kitchen exhaust, clothes dryers, fireplaces, etc
- Uses dedicated fan or bath fan to exhaust air from the home Exhausts air from only a localized area
- Replacement ventilation air comes from uncontrolled sources and is unevenly distributed
- Uncontrolled air sources can be highly contaminated
- Examples: garage, crawl space or attic