Fresh Air for better Indoor Air Quality

When people think about increasing the Indoor Air Quality of their homes, most probably think about pollutants like smoke/smog or allergens like pollen. Since these originate “outdoors”, the most logical thought is to close up your home as tight as possible and get an air cleaner of some sort. Although air cleaners like filters can and do help reduce the particles in the air to a varying degree, there is MORE to AIR quality than just “cleaning” the air.

The most critical and often overlooked aspect of having good indoor air quality is FRESH AIR. This, in it’s simplest form, is bringing outside air … inside. The first thought of objection might be that it seems counter-intuitive to bring air in that could have pollutants to try and “clean” the air, however, the EPA and other independant studies by AHRAE have shown that the pollutants like pollen can be 2 or 3x as high as outside air if a home is not properly ventilated. (see link below for sources and further explanation)

EPA recommendations for improving Indoor Air Quality: https://www.epa.gov/indoor-air-quality-iaq/improving-indoor-air-quality

A “properly ventilated” house includes both the intake of fresh air and the exhaust of inside air. Most homes come equipped with plenty of exhaust either in the bathrooms or kitchen vent hood but many do not have nearly enough intake of outside air. As a matter of fact, up until the 2000s, most homes were not equipped with any Fresh Air management at all which means that the only outside air that was coming inside was through cracks around doors and window. You might think this was an accident but it was actually “designed” this way because it has been know for 100 plus years that outside air is necessary for a healthy and clean air environment.

SmartZone-4X has a built-in FRESH AIR controller, that can be used to automatically (or manually) bring fresh air into the building. It was designed as a feature to meet the ASHRAE 62.2 standard but has many additional and useful features that make it more desirable than a standard “Fresh Air Control” like the Honeywell W8150.

Shown below, the SmartZone can be used as a “stand-alone” fresh air controller even without the need for any zoning.

Find out more and learn about the Adavanced Fresh Air control features: FRESH AIR - Enthalpy Control

Buy SmartZone-4X for your Fresh Air control

Ashrae 62-2 Ventilation (Fresh Air) sizing & calculation

Many homes these days have such tight seals around doors, windows, and even closed-cell foam insulation... they are almost air-tight.  You can think of an old house like an antique metal or wooden ice box where modern homes are more like Yeti coolers.  While this is great for keeping temperatures steady inside the home, it also can trap moisture and toxic gases inside.  Fresh air ventilation is necessary to keep a healthy and efficient home.

But how much fresh air is needed?  If you bring in too much, you will make your HVAC equipment work too hard and loose efficiency.  If not enough fresh air is brought into the home, the air can become humid and allow mold growth or VOCs and other toxins can build up.  Luckily, the national organization ASHRAE has a specific recommendation for the amount of air based on occupancy and square footage of the home.  See table below.

Taken from SmartZone-4X Install Guide

However, this table should not be taken as gospel.  Just like other HVAC calculations and estimations, many factors are not really being taken into account with this rough estimate based on # of bedrooms (occupancy) and square footage.  Some adjustments may be needed based on factors such as climate, ceiling height, other air-leakage, etc.  To comply with 62-2 is the baseline & adjustments can be made in the field by setting run-time.

Learn more about how SmartZone-4X can control fresh air more efficiently than a separate fresh-air controller in the Install Guide