Whole-home duct cleaning
Dryer vent cleaning
Camera inspection
Sanitizing & deodorizingWhole-system duct and dryer vent check with before-and-after photos - you see exactly what came out of your vents
That "$99 whole-house special" is a bait ad - the real number appears once they are in your hallway, or the "clean" is a shop-vac at the register. We photograph the inside of your ducts before and after instead.
Guardsman Vent Sanitizing: The Fort Worth Owner’s Guide
Guardsman vent sanitizing components are built to last, but when they fail, replacement is straightforward. We stock Guardsman-compatible sanitizing units and install them across Fort Worth for a flat written price of $285 to $475 depending on your system’s configuration. Most installations are completed the same day we arrive, and the work is covered by our 365-Day Done Right Promise in writing.
Most Fort Worth homeowners discover a problem the same way: the system cycles on, but airflow drops, or an odor they haven’t smelled before starts coming through the registers. In older homes near Ridglea Hills or the ranch-style neighborhoods southwest of the Stockyards, we often find sediment and mineral buildup from decades of hard water that’s slowly choked the sanitizing chamber. It’s not a dramatic failure. It’s a quiet one.
Which Guardsman Models This Applies To
The Guardsman vent sanitizing line spans a few configurations, and getting the right match matters. The most common units we service in Fort Worth are the in-duct UV sanitizer housings and the inline vapor chambers that mount just above the coil. The key identifier is the label on the housing: it will list a model prefix like GS, GSU, or GSX, followed by a three-digit series number. That series number tells you the lamp wattage and chamber length, and it is the single most important piece of information when matching a replacement.
Here’s the compatibility gotcha we see regularly: a Guardsman GS-300 and a GS-400 look nearly identical from the outside, but the lamp socket spacing differs by three-quarters of an inch. Installing the wrong part means the UV lamp doesn’t seat properly, and the sanitizing cycle never completes. We always confirm the model number and measure the chamber before quoting a replacement. For Guardsman specifically, we recommend OEM housings over generic aftermarket equivalents. The aftermarket shells are cheaper, but the gasket tolerances are sloppier, and in a Fort Worth summer when the attic hits 140 degrees, a loose gasket lets condensation into the electrical contacts. That’s a callback waiting to happen. We stock OEM Guardsman units on our trucks, along with compatible-quality replacement lamps.
Beyond Guardsman, we also carry parts for Lennox, Trane, and Carrier vent sanitizing systems for homes that have a mixed setup. Hollis Air Duct Fort Worth is an independent service provider and not affiliated with Guardsman, but the parts we install are factory-spec and matched to your unit’s series number.
Styles & brands we work with




Signs Your Guardsman Vent Sanitizing Is Failing
- A faint metallic or ozone-like smell from the registers. This usually means the sanitizing lamp is still drawing power but the chamber has developed a slow leak, exposing the filament to air. The lamp is oxidizing, and that smell is the result.
- Reduced airflow through specific vents. A failing sanitizer chamber can accumulate mineral scale that narrows the passage. You’ll notice it first in the furthest rooms from the blower, because the reduced pressure upstream starves the farthest registers.
- The indicator light on the unit is off or flickering. Guardsman units have a small diagnostic LED on the housing. A steady light means the cycle is completing. A flickering or dead light means the ballast is failing, which is a known wear item on GS-series units after six to eight years.
- Increased dust or allergy symptoms in the home. When the sanitizing chamber isn’t functioning, the air moving through the ducts isn’t being treated. For Fort Worth homeowners with cedar fever in the spring or dust from the dry summer months, this shows up quickly.
- The unit is warm to the touch near the baseplate. A properly running Guardsman unit should be cool or slightly warm. Significant heat at the baseplate indicates electrical resistance in the socket, which is a fire risk and should be addressed immediately.
See the difference
Before
After
Before
After
Before
AfterReplacement Cost & What’s Included
In Fort Worth, a complete Guardsman vent sanitizing replacement runs between $285 and $475 installed. The range breaks down like this:
- Replacement lamp only: $85 to $140 installed, when the housing and ballast are still sound.
- Full chamber and lamp replacement: $285 to $375 installed for standard in-duct units.
- Full unit replacement with upgraded ballast: $400 to $475 installed for larger homes with extended duct runs.
The price is written down before we start. It includes the part, labor, removal of the old unit, verification that the new unit cycles correctly, and a full year of coverage under our 365-Day Done Right Promise. If the part fails within that year, we return and make it right at no charge, including a free second visit. No moving targets, no surprise line items after the work begins.
DIY or Call Us?
There are a few things an owner can check safely. Confirm the model number on the housing label. Check whether the diagnostic LED is lit. Make sure the breaker to the unit hasn’t tripped. Those are reasonable homeowner checks.
What we don’t recommend is opening the housing yourself. The UV lamp in a Guardsman unit runs at high intensity, and the ballast stores charge even after the unit is disconnected. A wrong move with the lamp or the socket can result in a burn or an electrical shock. This is one of the few parts on a duct system that we genuinely ask homeowners to leave to a trained technician. If you’re seeing any of the warning signs above, call us at (682) 255-2572 and we’ll get it diagnosed and replaced. The estimate is free, and the price won’t move after we quote it.
FAQs
In Fort Worth, you can expect six to eight years from a Guardsman unit before the ballast or lamp gives out. The hard water in Tarrant County shortens the lifespan somewhat, because mineral scale builds up on the chamber walls and stresses the electrical components. If your unit is older than six years and showing symptoms, replacement is usually more cost-effective than repair.
Sometimes the lamp can be replaced independently if the housing and ballast check out, which costs $85 to $140. If the ballast has failed or the chamber is leaking, the repair rarely makes sense. The ballast on a GS-series unit fails because the internal capacitors degrade, and rebuilding it costs more in labor than a new OEM unit. Call us at (682) 255-2572 and we’ll tell you straight what’s worth fixing and what isn’t.
A standard Guardsman vent sanitizing replacement takes 45 to 90 minutes. That includes removing the old unit, installing the new one, cycling the system to confirm the diagnostic light is steady, and cleaning up the work area. We work in the attic or crawl space, so you won’t have equipment staged through your living room.
Yes. We carry OEM Guardsman chambers, lamps, and ballasts for the most common GS-series configurations on our trucks. That means most Fort Worth homes get the replacement done in one visit, not two. If your unit is an uncommon series, we’ll have the part in hand within a few days and install it the moment it arrives.
If your Guardsman vent sanitizing system is showing its age, don’t wait for the airflow problem to get worse. Call (682) 255-2572 for a free estimate. Written price before we start. Covered for a full year. No runaround.
Written by Roy Castellanos, Owner, Hollis Air Duct Fort Worth at Hollis Air Duct Fort Worth, serving Fort Worth and nearby areas.