Your ductwork is the part of your HVAC system you never see, which is exactly why problems there go unnoticed for years. Back2Cool HVAC offers air duct cleaning in Los Angeles along with duct sealing, repair, replacement and removal for homes and light commercial spaces across the San Fernando Valley and greater LA. We start with an honest look at what your ducts actually need.
When Air Duct Cleaning Is Worth It
Here is the honest part first: routine duct cleaning on a fixed schedule is not always needed. Ducts in a sealed system with good filters can stay reasonably clean for a long time, and a little dust on the inside of a duct is normal. But there are clear situations where cleaning makes a real difference:
- After wildfire smoke. The January 2025 Palisades and Eaton fires pushed smoke and ash into homes across LA. If your system ran during a smoke event, or you still notice a smoky smell when it turns on, fine soot may be sitting in your return ducts and on the coil.
- After a renovation. Drywall sanding, floor refinishing and demolition dust gets pulled straight into return vents, especially if the system ran during the work.
- Pests. Rodent droppings, nesting material or insects inside ducts, which is common in older homes with ducts in crawlspaces and attics.
- Visible debris or growth. Dust bunnies blowing from vents, dark buildup around registers, or growth on the inside of the duct or on the coil.
- A persistent musty smell when the system runs, which may also point to a moisture or drain problem we should track down.
- Moving into a home with an unknown history, especially after pets or heavy smoking.
For more on smoke specifically, read air duct cleaning after wildfire smoke in Los Angeles.
Before you book a cleaning: Replace your filter, then check whether the supply registers look dusty a week later. If dust keeps coming back fast, you may have a leaky return pulling in attic or crawlspace air. In that case, sealing is the real fix and cleaning alone will not last.
What Our Air Duct Cleaning Includes
- Inspection of supply and return ducts, registers and the return plenum before we start
- Floors covered and the work area protected
- Negative pressure applied to the system so loosened debris is pulled out, not blown into the house
- Agitation and cleaning of supply and return runs that are accessible
- Registers and return grilles removed and cleaned
- Return plenum and filter rack cleaned
- Inspection of the blower wheel and coil, with cleaning recommended if they are dirty, since a clean duct feeding a dirty coil does not solve much
- A walkthrough of anything we found: disconnected runs, crushed sections, pest damage or leaks
We also clean vents and grilles on their own for homeowners who just need the visible parts handled.
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$55 service call with code LA55 — inspection, diagnosis and a clear price before any work. Open 7 days · 8 AM – 10 PM.
Duct Repair: Leaks in Hot LA Attics
In many LA homes, ducts run through an attic that gets brutally hot in summer, especially in the Valley where triple-digit days are common. Every leak in that ductwork means you are paying to cool air and then dumping some of it into the hottest part of the house. Leaky return ducts do the opposite: they suck hot, dusty attic air straight into your system.
Common duct problems we find
- Flex duct disconnected from a boot or the plenum, sometimes blowing directly into the attic
- Crushed or kinked flex duct from attic foot traffic, storage or a past repair
- Old cloth tape that has dried out and fallen off joints
- Torn outer jackets and compressed insulation
- Undersized returns that starve the system for air
- Old ducts in crawlspaces damaged by pests or moisture
Signs your ducts need attention
- One or two rooms that never get comfortable
- Weak airflow from some vents and strong from others
- Dust that comes back quickly after cleaning
- A system that runs constantly in summer without keeping up
- Higher bills with no other explanation
Duct Sealing vs. Duct Replacement
| Sealing and repair | Replacement | |
|---|---|---|
| Good fit when | Ducts are in decent shape with leaks at joints, boots and plenums | Ducts are brittle, crushed, poorly insulated, badly routed or undersized |
| What we do | Reconnect runs, seal joints with mastic, repair or replace damaged sections | Design a new layout sized to the system, install new insulated ducts, seal everything |
| Typical timing | Often paired with a service visit or cleaning | Often paired with an AC or heat pump replacement |
We also remove abandoned ductwork, for example after a home switches to a ductless mini-split system, freeing up attic space and removing an old dust source.
Title 24 and Duct Leakage Testing
Under California's Title 24 energy code, altering or replacing ducts, and some equipment changeouts, may require duct leakage testing, often verified by a third-party HERS rater, depending on scope. A test pressurizes the duct system and measures how much air escapes. If leakage is too high, ducts need to be sealed until they pass before the permit can be closed out.
That testing is one of the steps cheaper bids quietly skip. We pull the permit, coordinate the test and seal to pass. Our guide to HVAC permits and Title 24 in Los Angeles explains when it applies.
How to Keep Ducts Cleaner Longer
Cleaning is a reset, not a cure. What keeps ducts clean afterward is the system around them:
- Use a filter that fits. A filter that is the wrong size lets air bypass it entirely. Gaps around the filter rack matter as much as the filter rating.
- Seal the return side. Leaky returns in an attic, garage or crawlspace pull in unfiltered dust and, in a garage, fumes.
- Protect vents during projects. Cover returns and turn the system off during sanding, demolition or painting.
- Keep the drain flowing. A clogged condensate drain keeps the coil area damp, which is often where musty smells start.
- Change filters after smoke events, not just on the usual schedule.
Ducts and Indoor Air During Heating Season
If your furnace blows a dusty or burning smell every time it starts, dirty ducts or a dirty heat exchanger may be the cause. Combine a duct inspection with a pre-winter heating check and you cover both. During smoke events, run the system on recirculate with a good filter and replace that filter afterward.
Duct Cleaning and Repair Across LA
We work in Sherman Oaks, Van Nuys, Pasadena, Beverly Hills, West Hollywood and throughout Los Angeles. Not sure whether you need cleaning, sealing or nothing at all? Call (626) 635-4095, 7 days a week, 8 AM to 10 PM, and we will give you a straight answer.
