Leaking, crushed, or disconnected ductwork can waste up to 30 percent of the conditioned air your system produces before it ever reaches a room. In Preston Hollow, TX, where homes range from mid-century ranch layouts to expansive custom builds, that lost air translates directly into higher energy bills, uneven temperatures, and equipment that runs far longer than it should. At M.B. Kiser Heating and Air Conditioning Co. Inc., duct repair is one of the core services we deliver to keep your comfort system operating the way it was engineered to.
How Air Loss Happens Inside Your Duct System
A duct system is a network of supply and return pathways that carries heated or cooled air from your central unit to every register in the home. Over years of thermal cycling, the metal expands and contracts, sealant tape dries out, and joints work themselves loose. Flexible duct runs sag or get pinched where they route through tight attic framing, restricting airflow to the rooms at the end of the line.
In older Preston Hollow properties, we frequently find original ductwork sealed with cloth-backed tape that has failed decades ago. The mastic and foil-backed sealants used today did not exist when many of these systems were installed. Rodents, remodeling projects, and insulation work also disturb duct connections, opening gaps that pull unconditioned attic air into the return side of the system. This drags in dust, humidity, and heat that your equipment must then work to remove.
Diagnosing Duct Problems Accurately
Guesswork wastes your money, so we approach every duct repair with a methodical inspection. We trace the full run of supply and return ducting, checking each transition, boot, and plenum connection. When symptoms point to hidden leakage, we use pressure testing to quantify how much air escapes and where.
Our technicians look for several specific conditions during an assessment:
- Separated joints: connections where duct sections have pulled apart or where tape has released from the metal collar.
- Crushed or kinked flex runs: flexible ducting that has collapsed under weight or been bent past its radius, choking airflow.
- Failed sealant: dried mastic, brittle tape, or gaps at the air handler and plenum that leak conditioned air into unconditioned space.
- Insulation gaps: bare or poorly wrapped ducts that allow heat transfer and encourage condensation in humid months.
Documenting these findings lets us give you a clear picture of the repairs needed and the priority order in which to address them. Sometimes a single loose plenum connection accounts for most of the loss, and a targeted repair restores balance across the entire home.
The Repair Methods We Use
Once we identify the problem areas, we match the repair method to the material and location. For sheet metal ducting, we reseal seams and joints with mastic and mesh, which cures into a durable, airtight bond that outlasts any tape. Where sections are damaged beyond sealing, we fabricate replacement pieces to fit the existing run precisely rather than forcing an off-the-shelf part into place.
Flexible duct that has been crushed or torn gets replaced with properly supported runs, secured with straps at the correct spacing so the duct does not sag between joists. We reconnect boots to registers, reseal the connection at the air handler, and verify that the insulation jacket is intact and continuous. On the return side, sealing is just as important, because leaks there pull attic contaminants straight into your living space and across your evaporator coil.
What Proper Duct Repair Delivers
Restoring duct integrity produces results you can feel and measure. Rooms that never seemed to cool down reach the thermostat setpoint. Your system cycles less often because it is no longer fighting against air escaping into the attic. That reduced runtime lowers wear on the compressor and blower motor, which extends the service life of equipment you have already invested in.
The benefits extend well beyond the utility bill:
- Balanced comfort: conditioned air reaches every room at the intended volume instead of pooling near the unit.
- Cleaner indoor air: sealed returns stop drawing in dust, allergens, and attic humidity.
- Lower operating cost: less air loss means the system delivers more of what it produces to the rooms that need it.
- Quieter operation: properly sized and sealed ducts reduce the whistling and rushing sounds that leaks and restrictions create.
These outcomes matter for both the residential and light commercial customers we serve. A small office suite or retail space with leaking ducts faces the same efficiency penalties as a home, and correcting them keeps operating costs predictable.
Experience You Can Rely On
M.B. Kiser Heating and Air Conditioning Co. Inc. has been in continuous operation since 1945, which makes us the oldest air conditioning company and the oldest Carrier Dealer in Dallas. That longevity means we have worked on nearly every type of duct system installed across the region over the past several decades, from original mid-century layouts to modern high-efficiency designs. We are family owned and operated, and we carry certification with Climate Master in addition to our long-standing Carrier relationship.
Our focus on maintenance contracts, repairs, and installations lets us build lasting relationships with the homeowners and property managers we work with. Duct repair often reveals broader system issues, and because we handle heating service, AC repair, air conditioning installation, and complete HVAC installation, we can address whatever we find without handing you off to another contractor. As the saying goes, it’s wiser to have Kiser install Carrier.
Reaching Us When You Need Help
Comfort problems do not keep business hours, so we do not either. Our call center handles after-hours calls, picks them up, and forwards them to our on-call technician and service manager. If your issue can wait until morning, we will call you first thing to schedule service at a time that works for you.
We provide duct repair and full HVAC service throughout Preston Hollow, TX and the surrounding communities of Dallas, University Park, Highland Park, Irving, Farmers Branch & Cockrell Hill, TX. Whether you have noticed a room that never cools, a spike in your energy bill, or airflow that seems weaker than it used to be, the ductwork is often the hidden cause. Contact M.B. Kiser Heating and Air Conditioning Co. Inc. and let our team restore the efficiency and comfort your system was built to provide.








