Enhanced Ventilation with Energy Recovery Ventilators (ERV)
Mechanical ventilation optimization for improved comfort and savings.
Tech Overview
Applicable Buildings Types multifamily, hotels
When to Implement at time of equipment replacement
*Be sure to consult a qualified service provider to determine the right measures for your building.
What are Energy Recovery Ventilators?
Many buildings have a mechanical ventilation system that uses fans to pull out stale air out of the building and bring fresh outdoor air into the building. An enhanced mechanical ventilation systems with an Energy Recovery Ventilator (ERV) with a Constant Airflow Regulator (CAR) dampers provides controlled and conditioned ventilation that improves indoor air quality and occupant health, while reducing greenhouse gas emissions and savings energy.
Fig 1. During winter, heat from the return air is transferred to the supply air in the heat recovery core (orange hatch) of an ERV. The flow of heat reverses in summer, where heat from the outdoor air is transferred to the exhaust air, helping to cool the supply air.
How to Implement
Mechanical ventilation systems are comprised of a number of components that should each be addressed when completing a high performance retrofit. A high performance retrofit typically includes cleaning and sealing ductwork, balancing airflow, upgrading fans with speed controls and installing ERVs. Download the full tech primer to learn more about each of the following steps:
A. Clean and Seal Ducts to avoid dust, dirt, and grime that accumulates inside air ducts, inhibiting airflow and depositing dust particles inside the building
B. Balance Airflow with Constant Airflow Regulator (CAR) dampers to avoid inconsistent ventilation across a building and irregular airflow
Fig 2. A Constant Airflow Regulator (CAR) automatically dampers airflow to achieve consistent ventilation.
C. Install Direct-Drive Fans with motor speed controllers to replace existing rooftop exhaust fans
D. Install Energy Recovery Ventilators (ERVs) that supply air into individual spaces to fully maximize energy savings
Cost and Benefits
Cost and benefits of an enhanced ventilation with energy recovery ventilators (ERV) will vary depending on your building’s baseline systems and conditions. Typically, buildings can expect to see the following results:
Greenhouse Gas (GHG) Savings
A high performance ventilation retrofit can reduce heating and cooling related GHG emissions.
Tenant Experience Improvement
A high performance ventilation retrofit can greatly increase tenant experience by effectively removing stale, contaminated air and delivering fresh, clean air to support occupant health and well-being.
Utility Savings
A small amount of utility savings can be achieved through the reduction of heating and cooling loads.
Capital Cost
A large capital investment is required for a ventilation retrofit that includes cleaning and sealing ducts, balancing air flow and installing ERVs.
Maintenance Requirement
Mechanical ventilation systems and ERVs require a low level of maintenance involving inspecting equipment and regularly cleaning the system.
Take Action
This information is part of more than a dozen High Performance Technology Primers prepared by the Building Energy Exchange and the Retrofit Accelerator to introduce decision-makers to solutions that can help them save energy and improve comfort in their buildings. Curious about other retrofitting possibilities? Explore our complete library of Tech Primers here.
The NYC Retrofit Accelerator’s team of Efficiency Advisors offers free, personalized advisory services to help streamline the process of making energy efficient improvements to your buildings.
Get in touch with the NYC Retrofit Accelerator today!
Call (212) 656-9202
Visit nyc.gov/RetrofitAccelerator
Email info @nycretrofit.org
