Energy Recovery Ventilator Calculator

Calculate efficiency, sizing, and cost savings for your ERV/HRV system

What is an Energy Recovery Ventilator?

Energy Recovery Ventilators (ERVs) and Heat Recovery Ventilators (HRVs) are systems that exchange heat between outgoing and incoming air streams, improving energy efficiency while providing fresh air ventilation.

Understanding Energy Recovery Ventilators

What’s the Difference Between ERVs and HRVs?

Both ERVs and HRVs recover heat from exhaust air, but they differ in their moisture handling:

  • Heat Recovery Ventilator (HRV): Transfers heat only between airstreams.
  • Energy Recovery Ventilator (ERV): Transfers both heat and moisture between airstreams.

ERVs are typically better for humid climates or when maintaining indoor humidity levels is important.

Benefits of Energy Recovery Ventilation

Energy Savings

Reduce heating and cooling costs by pre-conditioning incoming fresh air with otherwise wasted energy from exhaust air.

Improved Air Quality

Provide continuous fresh air while removing indoor pollutants, reducing CO₂, VOCs, and other contaminants.

Humidity Control

Help maintain optimal indoor humidity levels, reducing issues with condensation, mold, and comfort.

How ERVs/HRVs Work

Energy recovery ventilators use a heat exchanger core where outgoing and incoming air streams pass close to each other without mixing. This allows energy transfer between the airstreams while keeping the air separated.

Common ERV/HRV Core Types:

  • Fixed-plate: Simple, reliable design with no moving parts. Typically 50-80% efficiency.
  • Rotary wheel: Higher efficiency (up to 85%) but requires motor and more maintenance.
  • Membrane-based: Better moisture transfer for ERVs, good for variable climates.