Whole-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 Duct Repair & Sealing in Denver: What to Know First
We provide independent Guardsman duct repair and sealing in Denver, with most repairs scheduled within 2-4 business days and completed in a single visit. A written price is delivered before any panel comes off, and every job ends with a documented photo record of every duct run we touched. If you own a Guardsman air cleaner, humidifier, or integrated HVAC component and have noticed uneven airflow, whistling registers, or a spike in heating bills, the ductwork connecting that equipment to your living space may be the issue. Call (720) 799-2292 for a free estimate with no obligation to book.
How Guardsman Products Fail - and How We Fix Them
- Guardsman 5000 Series electronic air cleaners: The gasket seal between the air cleaner cabinet and the return plenum hardens after 6-10 Denver winters of low-humidity cycling. We see this in Park Hill and Hilltop homes where the original installation left a 1/4-inch gap. Our fix is removal, plenum surface prep, and reseating with fresh closed-cell gasket material rated for the temperature swing.
- Guardsman whole-home humidifier bypass ducts: The 6-inch round flex duct running from the supply plenum to the humidifier body collapses at the elbow where it leaves the main trunk. In Denver’s dry climate, the static pressure is higher than the Midwest ratings these units were originally spec’d for. We replace with insulated flex rated for the actual pressure load and support it with a proper saddle tap instead of the original snap-in collar.
- Guardsman HEPA 2400 return duct connections: The 1-inch filter rack on this series creates a turbulence point that loosens mastic seals upstream in the return duct run - the path that pulls air back to the furnace. We photograph the separation, reseal with water-based duct mastic (not foil tape, which fails in under 3 years here), and add mechanical fasteners at the joint.
- Guardsman UV-C light mounting collars: The 3-inch diameter port cut into the supply plenum for these lamps is often oversized by the original installer, leaving an annular gap that leaks conditioned air into the mechanical room. We fit a reducing collar sized to the actual lamp housing and seal with fiberglass-reinforced mastic.
- Guardsman ventilator intake hoods (ERV/HRV models): The exterior hood seal fails where the 4-inch PVC intake passes through the rim joist in Denver’s freeze-thaw cycle. We see frost buildup inside the duct at the first floor joist bay in Congress Park and Cheesman Park homes built 2015-2019. Our repair replaces the exterior caulk with silicone rated to -40°F and adds an interior fire-stop foam seal per Denver building code amendment R302.4.
Our Guardsman Duct Repair & Sealing Process

- 1
Call and schedule. A live person answers, confirms your Guardsman model if you know it, and books a diagnostic visit. No deposit required.
- 2
On-site diagnostic with photo documentation. The technician inspects every accessible duct run, plenum, and register connected to your Guardsman equipment. The camera goes in before any tool comes out.
- 3
Written scope and price. Haven Standard Clause 1: you receive a written price for the exact repair before work begins. If we find additional issues during the repair, we stop and write a new scope. No surprises.
- 4
Parts decision. For Guardsman-specific components, we source OEM when available and warranty-appropriate. For universal items like flex duct, mastic, and collars, we use quality aftermarket that meets or exceeds original spec. We note the choice on your written record.
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Repair, test, and document. The work is completed, pressure-tested where applicable, and the camera goes back in. You receive before-and-after photos of every run we touched as part of the standard job record.
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365-Day Done Right Promise in writing. If the seal fails or the repair doesn’t perform as scoped, we return and make it right. The promise is backed in writing, not subject to manager approval.
Before
AfterWhat Guardsman Duct Repair & Sealing Costs in Denver
These are honest ranges for Guardsman-specific duct repair and sealing work we’ve performed in Denver homes, based on 2013-2025 job records. Your written estimate will land in this range or we will explain exactly why your situation differs.
| Repair Type | Typical Range | What Moves the Price |
|---|---|---|
| Single register reseal (Guardsman air cleaner gasket) | $180-$260 | Accessibility, plenum material (galvanized vs. fiberboard) |
| Humidifier bypass duct replacement | $340-$520 | Duct length, insulation R-value, ceiling/floor penetration |
| Return duct mastic repair (HEPA 2400 turbulence point) | $280-$440 | Number of joints, extent of upstream separation |
| UV-C collar refit and seal | $220-$360 | Plenum location, existing hole condition |
| Ventilator intake hood reseal (freeze-thaw failure) | $260-$420 | Exterior access height, interior fire-stop requirements |
We do not quote per-vent or per-linear-foot teaser prices. One flat price per system, agreed before work starts. Call (720) 799-2292 for an exact quote - estimates are free.
Why Denver Homeowners Call CleanRun Air Duct Cleaning Denver for Guardsman Work

We’ve serviced Guardsman equipment in Denver since 2013, including jobs in Capitol Hill where original galvanized duct runs and older furnace systems make every repair a test of patience. Tomas Reyes, our owner, learned ductwork fundamentals at Apex Technical School in Manhattan and spent years in commercial and residential buildings across the Northeast before bringing that standard to Colorado. We also service Lennox, Trane, and Carrier systems, which matters when your Guardsman component is integrated with a mixed-brand HVAC setup and the failure point turns out to be at the interface, not the unit itself. Every technician is background-checked and uniformed under Haven Standard Clause 3: Verified Crews. Here is what the camera found. Here is what it costs to fix it. You decide.
FAQs
No, if the repair is performed using Guardsman-compatible parts and practices. As an independent Guardsman service provider, we are not affiliated with or authorized by Guardsman, and we follow manufacturer specifications for clearance, seal type, and component compatibility to keep warranty coverage intact where it applies. Call (720) 799-2292 if you want us to review your warranty terms before booking.
Most Guardsman OEM seals, gaskets, and collars ship to our Denver warehouse within 3-5 business days. For common failures like the 5000 Series gasket or HEPA 2400 filter rack, we stock quality aftermarket equivalents that meet original spec and can complete the repair on the first visit. We note OEM vs. aftermarket on your written record so you know exactly what was installed.
Repair the ductwork if the Guardsman component itself still functions and the failure is at the connection point - seal, collar, or flex duct. Replace the unit if the internal components have failed (power supply, cell pack, fan motor) and the unit is past 10-12 years. We will show you the camera evidence and give you a written price for both options so you can decide.
Your job record includes before-and-after photos of every duct run we touched, with timestamps. For repairs where pressure testing applies, we record the static pressure reading before and after. This is standard on every CleanRun visit, not an add-on. If you don’t receive your photo record within 24 hours of job completion, call us and we will resend it while you are on the phone.
Every 3-5 years in Denver’s climate, or sooner if you notice uneven heating, whistling at registers, or a sudden increase in utility bills. The freeze-thaw cycle and low humidity accelerate seal degradation compared to more temperate markets. We do not sell maintenance contracts - call (720) 799-2292 when you notice symptoms, and we will give you a free, no-obligation assessment.
Written by Tomas Reyes, Owner, CleanRun Air Duct Cleaning Denver at CleanRun Air Duct Cleaning Denver, serving Denver and nearby areas.




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