What is a heat recovery ventilator (HRV) and when would you use one instead of an energy recovery ventilator (ERV)?

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Multiple Choice

What is a heat recovery ventilator (HRV) and when would you use one instead of an energy recovery ventilator (ERV)?

The key idea is understanding what each ventilator recovers from the air streams. An HRV is designed to transfer sensible heat between the exhaust air and the outdoor air, which helps save energy by warming or cooling incoming air without changing its humidity. It does not transfer moisture. An ERV does the same heat transfer but also moves moisture between the air streams, helping balance indoor humidity in addition to temperature. So, you’d use an HRV when you mainly want to reclaim heat and avoid impacting indoor humidity, and you’d use an ERV when humidity control is also important or when you want to reclaim both heat and moisture to cut total energy use. The best description here is that an HRV transfers heat, while an ERV transfers both heat and moisture, which distinguishes their uses.

The key idea is understanding what each ventilator recovers from the air streams. An HRV is designed to transfer sensible heat between the exhaust air and the outdoor air, which helps save energy by warming or cooling incoming air without changing its humidity. It does not transfer moisture. An ERV does the same heat transfer but also moves moisture between the air streams, helping balance indoor humidity in addition to temperature.

So, you’d use an HRV when you mainly want to reclaim heat and avoid impacting indoor humidity, and you’d use an ERV when humidity control is also important or when you want to reclaim both heat and moisture to cut total energy use. The best description here is that an HRV transfers heat, while an ERV transfers both heat and moisture, which distinguishes their uses.

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