Smart Window Energy Recovery Ventilator

Your bedroom needs fresh air. Opening the window doesn't work.

Too hot. Too cold. Too loud. Too humid. Pollen, smoke, a busy street. So the window stays shut, CO2 climbs past 1,500 ppm overnight, and you wake up foggy with a headache.

SWERV sits in your window and fixes it: fresh filtered air in, stale air out, ~85% of your heat and AC kept inside. No contractor. Renter-friendly.

Ships the week of September 28 · 4 of 50 slots left


  • Engineered & Assembled in the USA
  • 30-Day Free Returns
  • 10-Minute Install
  • Renter-Friendly & Portable
Graph showing CO2 levels overnight with and without SWERV technology for two people sleeping in a closed room.
SWERV Window Mounted ERV Installed into beautiful white window organic with plants and an Aranet 4 air quality sensor to improve CO2 levels inside without wasting heat

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
Cutaway of the SWERV unit in a window: wood front facing the room, ceramic energy core in the middle, quiet fans facing outside 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 CO2 in your bedroom without opening windows

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

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

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

Optimize your sleep ➔
SWERV Filtered Window ERV Open Panel
Diagram of features including a powerful quiet fan, high-efficiency ceramic energy exchange core, sleek rotary dial, easy access MERV 13 air filter, thick foam insulation, and finished bamboo front panel.

Real customers, real CO2 numbers

J

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.

BM

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.

NA

Nate Adams

Nate Adams Click to view more
RA

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.

24 year-old Founder Building in Public

Austin Risenberger Founder of SWERV with visible skin conditions from mold sickness and text about mold sickness and high CO2 levels in a dorm room. View on Instagram
Columbia graduate Austin Riesenberger, Founder of SWERV, holding a SWERV product with a cityscape in the background of his college dorm View on LinkedIn
View on LinkedIn View on LinkedIn

Regular ERVs cost $10,000+ and require a major renovation.


SWERV is 10x cheaper and installs in 10 minutes.

Plus a 2-in-1 MERV 13 + activated carbon filter blocks wildfire smoke and pollen on the way in.

Preorder Now ➔
Comparison chart of different HVAC products with their features and specifications.

Ventilation Without Renovation

Designed, Built, and Tested by our Team of Engineers in Boston

As seen on

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