Close-up of a moisture-covered HVAC evaporator coil behind an air handler panel
Your House's HVAC History

Your HVAC Doesn't Just Cool Your Room.

It also pulls moisture out of the air. That moisture lands on the coil – cycle after cycle.

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This Is Your Coil.

Tucked behind the vent, out of sight. It's the one part of your HVAC system every bit of air in your home actually touches on its way through. Everything below happens right here.

The Problem

Here's What That Process Leaves Behind.

Water, on repeat

Every time your system runs, more moisture condenses here. It doesn't fully dry before the next cycle starts.

Technician in a black glove opening an air handler to inspect the coil

Which is exactly what mold needs

Cooling and removing moisture are the same process – the water it pulls out has to condense somewhere.

And it doesn't stay put

Once mold takes hold, it releases allergens and irritants into the airstream – the same air moving past the coil, into your ducts, and out your vents.

Sometimes it's visible before it's diagnosed

Mold near your system's intake is often the first sign of a larger humidity or ventilation issue, not just a surface-level coil fix.

Why It's Unhealthy

The Air in Your Rooms Passed Through the Coil First.

The mold growing in the coil doesn't stay there. It rides the same air your system pushes into your house.

Living room with particles drifting from a wall supply vent

It's in the air that you breathe

Allergic reactions, asthma, and other respiratory symptoms are among the potential effects of mold exposure.

Woman wrapped in a blanket on a sofa using a tissue

It can trigger existing conditions

For people already sensitive to it, inhaling mold spores can trigger or worsen asthma symptoms.

Family on a sofa covering their faces beside a mold-spotted wall vent

It adds up over time

Musty, mold-affected air is a recognized contributor to "sick building syndrome" – linked to lower productivity, poor morale, and higher healthcare costs.

What It's Costing You

A Dirty Coil Makes Your Compressor Work Overtime As Well.

It keeps collecting debris, and the buildup compounds – increasing energy use and utility costs while shortening the system's lifespan.

7-11 Years

for an unmaintained coil to double its airflow resistance – decades before its expected 15–30 year lifespan

Lawrence Berkeley National Laboratory
5-20%

potential energy savings from well-maintained HVAC operations vs. neglected systems

U.S. DOE Federal Energy Management Program
One Root Cause. One Fix.

A Specific Wavelength Of Light Stops The Problems At The Coil.

UV-C is light at 253.7 nanometers – the same germicidal range hospitals use to sterilize surfaces. Aimed directly at your coil, it's absorbed by the DNA of mold and bacteria on contact, stopping them from reproducing.

A visibly cleaner coil
Less pressure drop across the coil
Improved heat transfer efficiency
UV-C lamp glowing inside an air handler, aimed across the evaporator coil

The alternative -  a $150+ service call every year – and the mold's usually back within months. UV-C runs continuously, so there's nothing to schedule and nothing that regrows in between.

How It's Set Up

Install Once. Let The UV-C Run On Its Own.

UV-C unit mounted beside the coil inside an air handler cabinet

Mounted near the coil

Allergic reactions, asthma, and other respiratory symptoms are among the potential effects of mold exposure.

UV-C lamp casting light straight along the length of the coil

Direct line of sight

UV-C doesn't bend around corners, so it's aimed straight at the coil.

Magnetic-mount UV-C unit being fitted without drilling

Wired in, or magnetic

No drilling required with the magnetic mount option.

Installed BioShieldUV controller running on the side of a duct

Starts running in 15 mins

Start to finish, no contractor required.

Lab Tested

Proven In The Lab.
Not Just On The Label.

Here's what our UV-C looks like under test conditions:

>99%
Mold growth prevented
(Aspergillus niger)
>99.999%
Bacteria eliminated
(Staphylococcus aureus)
UV-C light sweeping a coil seeded with mold and bacteria under test conditions

Independently tested – Intertek Columbus Microbiology Lab, ASTM E3135

See How UV-C Works
Intertek lab technician working at a microscope
Our Promise

Cleaner Coil In 90 Days.
Or You Get Your Money Back.

Not visibly cleaner in 90 days? Full refund, including shipping. The unit is yours to keep either way.

✓ CoilPledge™ Guarantee
Side-by-side coil comparison: heavily fouled on day 0, clean on day 90
Day 0 Day 90
Why Homeowners Trust Us

10,000+ Families Protected

ETL Listed mark

Safe to run 24 hours a day

ETL Listed under UL 60335-2-40 for continuous operation. Applies to 18W and 36W models only.

Intertek mark

Proven to work on real mold

ASTM E3135 lab tested at Intertek Columbus.

RoHS Certification mark

Free of harmful materials

RoHS compliant with no restricted hazardous substances inside the device.

FCC mark

Doesn't disrupt your smart home

FCC certified so your WiFi, thermostat, and other electronics stay unaffected.

CE mark

Meets Global safety standards

CE marked to the stricter European safety benchmarks.

United States Environmental Protection Agency seal

Tracked from factory to your door

EPA Establishment Number on file with full batch-level traceability.