Balanced Ventilation

Balanced ventilation is an HVAC strategy that maintains equal volumes of fresh air supply and stale air exhaust, creating optimal indoor air quality while maximizing energy efficiency. Unlike traditional single-direction systems, balanced ventilation actively controls both incoming and outgoing airflows through dedicated fans and heat recovery mechanisms.

Table of Contents

Core Operating Principle
Air Exchangers
Types of Balanced Ventilation Systems
Heat Recovery Ventilator (HRV)
Energy Recovery Ventilator (ERV)
Dedicated Outdoor Air Systems (DOAS)
Technical Specifications
Installation and Maintenance Considerations
Design Requirements
Maintenance Protocol
Economic Benefits

Core Operating Principle

The system operates on a simple but powerful concept: for every cubic meter of fresh outdoor air brought into a building, an equal volume of indoor air is exhausted. This balance prevents pressure imbalances that can cause drafts, door slamming, or infiltration issues while ensuring consistent air quality throughout the space.

Key Components:

Supply fan: Brings fresh outdoor air into the building
Exhaust fan: Removes stale indoor air
Heat recovery ventilator (HRV): Transfers thermal energy between airstreams
Filtration system: Cleans incoming air
Smart controls: Monitor and adjust airflow rates

Air Exchangers

Air exchangers do exactly what their name implies: they exchange stale indoor air with fresh air from the outside. Although the energy savings derived from using an air exchanger is often minimal, the benefits to occupants are significant. As buildings have become tighter, less air moves through leaks around windows, doors, chimneys, etc. This can lead to an unhealthy build-up of odors, carbon dioxide, or volatile organic compounds (VOC). Opening a window may allow fresh air in, but at a considerable energy loss. Air exchangers provide the fresh air needed for occupants and minimize the energy losses for heating or cooling.

Heat recovery ventilation (HRV) is a system that exhausts air from inside of a home and replaces it with outdoor air. During this process the system captures heat from the air being exhausted and uses it to preheat the air entering the home. The air flows (fresh and exhaust) don’t mix.
Energy recovery ventilation (ERV) is a system that does everything that an HRV does with the addition of transferring moisture from the exhausted air into the air entering the home (in the winter) and restricting moisture from incoming air (in the summer). This can provide higher comfort for occupants by balancing the humidity levels inside the home.

Types of Balanced Ventilation Systems

Heat Recovery Ventilator (HRV)

A Heat Recovery Ventilator (HRV) is an essential component in modern HVAC systems, particularly valued for its ability to improve indoor air quality and energy efficiency. This device works by exchanging the stale indoor air with fresh outdoor air, while simultaneously transferring heat between the streams to recover a significant portion of the energy that would be lost in the process. This heat exchange process is pivotal during colder months, as it pre-warms the incoming air, reducing the load on the heating system, and in turn, lowering energy costs. Furthermore, HRVs are designed to balance the indoor humidity levels, thereby mitigating issues such as mold growth and promoting a healthier living environment. As energy efficiency becomes increasingly paramount in building design, HRVs are gaining traction, aligning with standards and compliance directives focused on sustainable and efficient building practices.

Transfers sensible heat between incoming and outgoing airstreams. Ideal for heating-dominated climates where moisture removal isn’t critical.

Energy Recovery Ventilator (ERV)

An Energy Recovery Ventilator (ERV) is a sophisticated HVAC component designed to enhance indoor air quality and optimize energy efficiency in residential and commercial buildings. By utilizing a heat exchanger, an ERV captures thermal and latent energy from stale outgoing air and transfers it to fresh incoming air. This process moderates the temperature and humidity of the incoming air, reducing the load on heating and cooling systems and ultimately lowering energy consumption. ERVs are particularly beneficial in climates with significant humidity variations, as they efficiently manage moisture levels while maintaining ventilation. Integrating ERVs into HVAC systems not only promotes a comfortable indoor environment but also supports sustainable building practices by decreasing reliance on energy-intensive temperature conditioning.

Recovers both sensible and latent heat, managing humidity alongside temperature. Essential for hot, humid conditions or spaces with high moisture generation.

Dedicated Outdoor Air Systems (DOAS)

Dedicated Outdoor Air Systems (DOAS) are innovative HVAC solutions designed specifically to manage fresh air ventilation and improve indoor air quality across various building environments. Unlike traditional HVAC systems that combine heating, cooling, and ventilation, DOAS focus solely on bringing in and conditioning outdoor air independently from the temperature control processes. This separation allows for more precise humidity control and significant energy savings, as it enables the primary HVAC system to concentrate on space conditioning without the additional burden of ventilation loads. DOAS are particularly beneficial in modern, airtight buildings where maintaining the optimal exchange of fresh air is crucial for occupant comfort and health. By efficiently integrating heat recovery technologies, DOAS can further enhance sustainability by reducing the energy required to condition incoming air while simultaneously meeting or exceeding the latest industry standards for indoor air quality.