Smart Window Energy Recovery Ventilator

Your stuffy bedroom needs fresh air.

Open windows let in heat, humidity, cold, dryness, pollution, pollen, and street noise.

Closed windows trap stale air, so your bedroom feels stuffy, CO2 builds up, and you wake up feeling foggy with a headache.

SWERV supplies fresh filtered outdoor air without any of the bad stuff, giving you control over your home environment.

Preorder SWERV V3 ➔ Call the Founder

SWERV V3 · Ships February 2027

Engineered & Assembled in the USA
30-Day Risk-Free Trial + 5-Year Warranty
10-Minute Install
Renter-Friendly & Portable

Graph showing CO2 levels overnight with and without SWERV technology for two people sleeping in a closed room.

A wood-look window ERV air exchanger with a white side panel and a black power cord, placed on a white windowsill next to a window showing green trees outside.

How it works

Exchanges stale indoor air for fresh outdoor air with energy recovery.

INSIDE

Room air 70°F 50% humidity Air delivered 59°F 55% humidity

Core storing heat

OUTSIDE

Outdoor air 0°F 20% humidity Outdoor air 0°F 20% humidity

Stale room air pushed out Filtered fresh air pulled in

Always running, one direction at a time, reversing every 45 seconds

Reduce bedroom CO2 without opening windows

Closed windows wake you up feeling foggy with a headache. Open windows waste energy and comfort, letting in heat, humidity, cold, smoke, pollution, pollen, and street noise.

Customers with CO2 monitors routinely measure overnight drops of 600+ ppm.

SWERV recovers ~85% of the energy an open window throws away, it can pay for itself in 1-2 years.

Optimize your sleep ➔

SWERV Window Mounted Air Exchanger ERV Video of front panel opening and closing

A feature infographic diagram for a portable window air exchanger energy recovery ventilator ERV, showing teal arrows pointing to labeled features: Quiet Powerful Fans, Window Bracket, Efficient Ceramic Core, Dial Interface, Real Bamboo Front Panel, MERV-13 + Activated Carbon Air Filter, and Thick Foam Insulation, on a white background.

Reviews + Data

Josh

The SWERV beta unit has had a significant and noticeable impact on air quality. Before, our bedroom was peaking at over 1900ppm CO2. The average CO2 after install is now 784ppm.

We have had much better sleep overall. The most notable change is that we rarely have headaches when we wake up. The reduction in headaches alone has been amazing.

Blake M.

I now maintain between 600-800ppm with all the windows closed and my home is much quieter and cleaner.

The big change has been having a quieter environment. It also gets pretty cold here, but the ERV has allowed me to control the indoor climate much more effectively than before.

Nate Adams

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Remington A.

It's been incredible. CO2 averages around 400-600ppm throughout the house with one unit at 26-40%. We were only able to achieve these levels if we were both out of the house at the same time.

My girlfriend and I have been able to do hard workouts on our Tonal for weeks without feeling sick. It's the first time I feel like I can actually use it again.