LC Heating & Air provides expert duct sealing for San Marino homes, helping you stop energy loss, balance room temperatures, and ensure your HVAC system runs efficiently.
Duct Cleaning & Air Duct Service in San Marino
LC Heating & Air provides duct cleaning in San Marino — including air duct cleaning, duct repair service, duct sealing, HVAC ductwork. Whether you need same-day service, a written estimate, or help deciding between repair and replacement, our licensed technicians handle every make and model.
We repair and service all major HVAC brands in San Marino, including Carrier, Trane, and Goodman, and older or discontinued units. No matter the manufacturer, we diagnose the problem accurately and give you an upfront price before any work begins.
I'm Leo, owner of LC Heating & Air. If you're living in San Marino, you know that our hillside homes and unique architecture can make climate control a real challenge. Often, the problem isn't just the furnace or the AC unit itself—it's the ductwork. If your conditioned air is leaking into your attic, crawl spaces, or wall cavities before it ever reaches your living room, you're essentially paying to heat or cool the outdoors.
At LC Heating & Air, we focus on the practical side of HVAC. We don't believe in selling you a new system if your current one just needs a proper seal. Whether you're dealing with uneven temperatures in different rooms or your energy bills are higher than they should be, I'll come out, inspect your ducts, and give you an honest assessment of whether sealing will solve your comfort issues.
Call LC Heating & Air at (323) 970-3113 for scheduling and estimates.
Local HVAC considerations
Why Duct Sealing Matters in San Marino
San Marino's housing stock—ranging from older custom homes to hillside properties—often features ductwork that has been compromised by time, settling, or poor initial installation. In these homes, we frequently find that duct leakage is the primary culprit behind room-by-room comfort differences. Because of the sun exposure and elevation changes common in our area, your HVAC system is already working hard; losing 20% or more of your airflow to leaks makes that job impossible.
When we inspect a home, we look for the signs: dust buildup near registers, HVAC cycles that never seem to end, and rooms that stay hot or cold regardless of the thermostat setting. In many cases, sealing these leaks is the most cost-effective way to get the performance you expect from your equipment.
Working with San Marino Architecture
I understand that working in San Marino homes requires a different approach. We deal with tight-access mechanical areas, complex attic layouts, and delicate finishes. My team and I are careful to plan our access—whether it's ladder placement or navigating narrow crawl spaces—to ensure we get the job done without disrupting your home.
We don't treat every house the same. We take the time to look at how your duct runs are routed and where the heat gain is happening. This context is vital because it changes the repair decision. If the ducts are structurally sound but leaking at the joints, we seal them. If the ductwork is crushed or failing, we'll tell you that sealing isn't the right fix.
Our Diagnostic Process
We don't guess. Before we touch a single joint, we perform a duct blaster test. This gives us a quantitative measurement of your leakage as a percentage of your total airflow. It tells us exactly how much air you're losing.
Once we have the data, we decide on the best approach. Sometimes, manual mastic sealing is the right move for accessible joints and plenums. Other times, we use the Aeroseal process to reach the leaks hidden inside your walls or ceilings. We finish every job by re-testing the system so you can see the difference in black and white.
Repair vs. Replacement: An Honest Look
A lot of contractors will push for a full duct replacement the moment they see a leak. That's not how I operate. If your existing duct system is in good shape, sealing it is a permanent, high-value solution that can last for the life of the system.
However, if I find that your ducts are undersized, crushed, or made of materials that are falling apart, I will tell you that sealing is just a band-aid. My goal is to provide a solution that makes sense for your home and your budget. If a repair is enough to get you comfortable, that's what I'll recommend.
Understanding the Costs
I believe in transparency. Duct sealing costs vary based on the size of your home and the accessibility of the ducts. Manual sealing typically ranges from $400 to $1,200, while the Aeroseal process for a typical single-story home runs between $1,500 and $3,000. These costs include the diagnostic testing and the verification testing.
When you consider that sealing 20–30% of duct leakage can reduce your HVAC energy use by 15–25%, the payback period is often quite short. We provide a written estimate after our initial inspection so you know exactly what you're paying for before we start.
Safety and Indoor Air Quality
Your health is the priority. When we use Aeroseal, we use a non-toxic polymer—the same material found in chewing gum—that is safe for your home. We also ensure that your system is clean before we seal it. Because we are a licensed C-20 HVAC contractor (CSLB #1073586), we follow all safety protocols to ensure your indoor air quality is protected throughout the process.
Avoid These Common Mistakes
The biggest mistake I see is homeowners using standard silver 'duct tape' to seal leaks. That tape dries out and fails within a few years. We use professional-grade mastic that stays flexible and adheres permanently. Another mistake is skipping the duct blaster test; without it, you have no way of knowing if the work actually solved the problem or if you're just paying for someone to tape over a few visible holes while the real leaks remain hidden.
Scheduling Your Service
We know your time is valuable. We offer same-day service options and clear communication regarding our arrival. Given the unique access requirements in San Marino—like narrow roads and hillside slopes—we always ask about your property layout when you call. This helps us bring the right equipment the first time, ensuring we don't waste your day.
Is Duct Sealing Right for You?
If your HVAC system is running constantly but your home still feels uneven, or if your utility bills have spiked without a change in your habits, it's time to look at your ducts. Sealing is a practical, high-ROI investment that addresses the root cause of air loss.
If you're planning an HVAC replacement, I highly recommend testing your ducts first. California Title 24 requires duct leakage testing for new systems, and it's much easier to address these issues while we're already working on your equipment. Give us a call at (323) 970-3113, and let's talk about your home.
How the visit works
We perform a duct blaster test to quantify existing leakage as a percentage of system airflow.
Based on leakage quantity, duct type, and accessibility, we recommend manual sealing, Aeroseal, or a combination.
We apply mastic to all accessible joints and plenums, or set up and run the Aeroseal process for internal sealing.
We re-run the duct blaster test and provide you with before/after leakage numbers as written documentation.
Cost factors we review before quoting
- • Duct inspection: $125–$200
- • Manual mastic sealing: $400–$1,200
- • Aeroseal internal sealing: $1,500–$3,000
- • System accessibility and complexity
Useful next steps
Duct Sealing in San Marino at a glance
- • Duct Sealing provider: LC Heating & Air
- • Location served: San Marino, CA 91108
- • License: CSLB C-20 #1073586
- • Phone: (323) 970-3113
- • Estimate: written estimate before approved work
- • Emergency calls answered within 30 minutes (24/7)
Our duct sealing process in San Marino
Reviewed by Leo, Owner & Lead Technician
This duct sealing guide for San Marino is reviewed for practical HVAC accuracy by Leo at LC Heating & Air. LC Heating & Air holds California CSLB C-20 HVAC license #1073586 and provides written estimates before approved work.
What San Marino customers say about duct sealing
Verified reviews from homeowners in San Marino and nearby neighborhoods who used our duct sealing service.
“AC wasn't cooling to setpoint even though it was running all day. LC found the condenser coils were completely clogged with cottonwood. Cleaned them on the spot and the system cooled my house 12 degrees in an hour.”
“LC replaced our entire HVAC system — new Carrier condenser, furnace, and coil. Leo walked us through every option without pressure. The install team was professional and clean. System runs perfectly and our electricity bill dropped about 30%.”
“Called LC because our CO detector went off. Their technician found a crack in the heat exchanger and immediately shut down the furnace. He explained the safety issue clearly, provided a replacement estimate, and didn't try to scare us — just facts.”
