Modern Air Systems provides HVAC service in San Marcos, including AC repair, full system replacement, heating repair and maintenance. We are a family-owned company with more than 25 years of HVAC experience in our family, and we give every customer an honest, repair-first opinion.
HVAC in San Marcos: The Short Answer
Modern Air Systems provides AC repair, HVAC system replacement, heating repair and maintenance in San Marcos, TX, for homeowners, landlords and small businesses. We are a family-owned, licensed HVAC company that serves the area from our San Antonio base along I-35, with written pricing before any work starts.
HVAC Services in San Marcos
- AC repair for systems that are not cooling, leaking or freezing up
- Full HVAC system replacement for split systems, heat pumps and packaged units
- Furnace and heat pump repair before the first cold front
- Spring and fall tune-ups and the Comfort Club maintenance plan
- Ductwork repair and replacement
- Thermostat installation
- Light commercial HVAC for small businesses
- Second opinions on HVAC quotes
Most-requested services in San Marcos: AC repair, HVAC system replacement, maintenance and the Comfort Club, heating and furnace repair and light commercial HVAC.
Common HVAC Problems in San Marcos Homes
Central Texas heat and humidity make a few problems especially common:
Problem, cause and where to start
Five issues we see most in San Marcos homes
| Problem | Common cause | Where to start |
|---|---|---|
| AC running but not blowing cold air | A failed capacitor or low refrigerant | AC repair |
| Ice on the refrigerant lines | Airflow problems or low charge | AC repair |
| Water leaking indoors | A clogged condensate drain | AC repair or Maintenance |
| Upstairs much hotter than downstairs | Common in two-story homes | Ductwork repair |
| High electric bills | Aging systems or leaky ductwork in hot attics | Ductwork repair or System replacement |
HVAC for San Marcos Rentals and Landlords
San Marcos has a large rental market, much of it serving Texas State students. We work with landlords and property managers on tenant repairs, turnover checks and maintenance, with clear records and approval limits for repairs.
Same-Day Price Estimates for System Replacement
Thinking about a new system? Send a photo of the nameplate on your outdoor and indoor units, and we can send a same-day price estimate. Your final price is confirmed after an in-home or photo-based assessment. Financing is available for qualified homeowners.
Why San Marcos Homeowners Choose Modern Air Systems
- Licensed and insured, Texas license TACLB27872E
- Family-owned, with three generations of HVAC experience
- Written, upfront pricing before work starts
- A 1-year labor warranty on system replacements
San Marcos Neighborhoods and Nearby Areas We Serve
We work across the city, from homes near downtown and the Texas State University area to newer subdivisions on the edges of the city. We also serve nearby communities in Hays and Comal counties, including Kyle, Buda and New Braunfels.
AC Repair in San Marcos
When your AC stops cooling, we diagnose the problem before recommending anything. Common repairs include failed capacitors and contactors, refrigerant leaks, frozen coils, clogged drains and worn fan motors. Learn more about our AC repair process.
HVAC System Replacement in San Marcos
If your system is 12 to 15 years old or needs a major repair, replacement may cost less over time. We size every new system for your home, explain your options and help you register equipment for manufacturer warranty coverage. See our HVAC system replacement page for details.
Heating Repair in San Marcos
Winters here are short, but a furnace or heat pump that will not start on a cold night still needs fast attention. We repair gas furnaces and heat pumps and check safety controls and venting. See our heating and furnace services.
HVAC Maintenance in San Marcos
Spring and fall tune-ups keep your system ready for the long cooling season and the first cold front. Ask about the Comfort Club maintenance plan for local homes and rentals.
Why Licensing Matters in San Marcos
Every HVAC contractor in Texas must hold a license from the Texas Department of Licensing and Regulation. You can verify our license, TACLB27872E, before you schedule service.
Frequently Asked Questions
Do you serve San Marcos, TX?
Yes. We provide AC repair, HVAC system replacement, heating repair and maintenance in San Marcos and nearby Hays County communities.
Do you work on rental properties near Texas State?
Yes. We work with landlords and property managers on rental homes and small multifamily properties in San Marcos.
Can you give me a price for a new system from a photo?
Yes. Send a clear photo of your equipment’s nameplate, and we can send a same-day price estimate, confirmed after a short assessment.
Do you offer maintenance plans in San Marcos?
Yes. Ask about spring and fall tune-ups and the Comfort Club maintenance plan.
How fast can you get to San Marcos?
We schedule service calls as quickly as our schedule allows during business hours. Call or request service online for the next available time.
Do you charge a trip fee to San Marcos?
Ask our team about current service call pricing when you book. You will know the cost before we arrive.
Do you service small businesses in San Marcos?
Yes. We repair and maintain light commercial HVAC, including rooftop and packaged units, for local small businesses.