Healthy schools: HVAC tips for winter

Heating, Ventilation and Air Conditioning system keeps schools comfortable in colder months

Poor indoor air quality in schools may affect health and
well-being of students, teachers and staff.

Quality HVAC system design, operation and maintenance are critical for providing healthy IAQ in schools.

Properly functioning HVAC systems provide adequate ventilation, control odors and reduce the pollutants that cause most IAQ problems inside school buildings. In addition to improving occupant health and performance, regular HVAC maintenance saves energy.


In anticipation of the colder months, schools should pay special attention to their HAVC units, including:

• Be aware of indoor humidity levels as the outside temperature drops. To protect health, comfort, the school building and its contents, it is important that indoor relative humidity be maintained below 60%, ideally between 30% and 50%.

Did You Know?

In colder climates, there can be operating conditions which will cause freezing within the energy recovery heat exchanger and it is often necessary to equip ERV systems with a frost control option.

• Ensure that facilities and maintenance staff change filters on a regular basis. Air filters should have a dust-spot rating between 35% and 80% or a Minimum Efficiency Rating Value (MERV) between 8 and 13 depending on the compatibility of your air handling unit. The higher the MERV rating, the more particulates will be filtered.
• Ensure proper ventilation as there are significant spatial and seasonal variations in the volume of air delivered by most HVAC systems. Learn more by checking out the ASHRAE Standard 62-2013.
• Have a plan to ensure HVAC systems are functioning property over winter and holiday breaks. With intermittent building occupancy over breaks, outdoor air ventilation rates may need to be adjusted. Check all air registers to ensure that they are not obstructed by furniture or large objects that may have been moved inadvertently.

HVAC Resources

Checklist: Download and use the ventilation checklist. Tailor it to fit the needs of your individual school or district.

Software: The School Advanced Ventilation Engineering Software (SAVES) package is a tool to help school designers assess the potential financial payback and indoor humidity control benefits of Energy Recovery Ventilation (ERV) systems for school applications. Both SAVES software tools (the Energy Recovery Ventilation Financial Assessment Software Tool (EFAST) and the Indoor Humidity Assessment Tool (IHAT)) can be downloaded here.

Standards: School HVAC systems should be designed and operated to provide a minimum outdoor air ventilation rate consistent with current ASHRAE Standards 62.1. For classrooms, this standard is about 15 cubic feet per minute (cfm) of outdoor air per person.

Webinars: Poorly maintained HVAC units can lead to IAQ problems, such as mold issues. For additional information on how to create healthy learning environments in the winter, download the two webinars, Mold and Moisture: Double Trouble for Schools and Integrated Pest Management (IPM) in Schools - Basics for Winter.

Source: EPA

Protect school's IAQ with air cleaners

While the HVAC system plays a major role in keeping a school's indoor air environment healthy and comfortable, many educational facilities are plagued by poor indoor air quality, which can negatively affect students, teachers and staff.

Electrocorp's RAP series
provide cleaner air.

Health, well-being and productivity may suffer when the air contains high levels of VOCs, mold, bacteria, viruses, allergens, particles and chemical fumes.

Apart from source control and ventilation, schools can improve their indoor air quality with a few well-placed indoor air cleaners. Electrocorp has designed a variety of indoor air purifiers for schools and universities that provide cleaner and more breathable air all day long.

The air cleaners feature a comprehensive activated carbon and HEPA air filter system, which removes a wide range of chemicals, odors, particles, dust, allergens and fumes.

Optional UV germicidal filtration helps neutralize biological contaminants such as bacteria, viruses and mold.

For more information, contact Electrocorp and speak to an IAQ expert.