HVAC System Replacement in San Antonio

HVAC system replacement is the removal of your old air conditioner, heat pump or furnace and the installation of new, matched equipment sized for your home. In San Antonio, most homeowners replace when a system is 12 to 15 years old, needs a major repair, or still runs on R-22 refrigerant. Modern Air Systems gives you a same-day price estimate from a photo of your nameplate, then confirms the final price after a short assessment.

A full HVAC system replacement means changing the matched parts of your heating and cooling system together, not just one box. Depending on your home, that can include:

• The outdoor condenser or heat pump
• The indoor evaporator coil and air handler, or a gas furnace
• A packaged unit, where everything sits in one cabinet outside or on the roof
• A new thermostat matched to the equipment
• Line set, drain line, electrical disconnect and pad checks, with repairs where needed
• Duct connections, sealing and airflow checks at the supply and return

Replacing matched equipment together matters. An outdoor unit paired with an old, mismatched indoor coil often cannot deliver its rated capacity or efficiency, and it can shorten the life of the new compressor.

You do not have to wait days for a quote. Text or email us a clear photo of the nameplate (the metal label) on your outdoor unit and your indoor unit, and we can send a same-day price estimate for HVAC system replacement.

The nameplate tells us the model, size and age of your current equipment. From there we can price a comparable system and show you options. Your final price is confirmed after a short in-home or photo-based assessment, because ductwork, electrical, attic access and code items can change the scope. We always explain any change in writing before work starts.

Most San Antonio homes have one of two layouts, and HVAC system replacement works differently for each.

We replace both. If you are not sure which you have, the photos you send us will show it.

Bigger is not better. An oversized system cools the air quickly, shuts off before it removes humidity and leaves rooms feeling clammy. An undersized system runs constantly on hot afternoons and still cannot keep up.

The International Residential Code (section M1401.3) calls for heating and cooling equipment to be selected using a load calculation such as ACCA Manual J, with equipment chosen using ACCA Manual S or another approved method. We look at your square footage, insulation, windows, sun exposure and ductwork before we recommend a size, instead of simply copying the tonnage on your old unit.

These are the questions San Antonio homeowners ask us most often when they are deciding.

• Your system is 12 to 15 years old or more and needs another major repair
• The compressor, coil or heat exchanger has failed
• Your system still uses R-22 refrigerant, which has not been produced or imported in the U.S. since 2020
• Your energy bills keep climbing even though your habits have not changed
• Some rooms are always too hot, too cold or too humid
• You are paying for repairs every season

A useful rule of thumb is the $5,000 rule: multiply the age of your system by the repair cost. If the result is over $5,000, HVAC system replacement usually makes more financial sense than another repair. We will walk you through the numbers honestly.

The cost of HVAC system replacement in San Antonio depends on:

• System type: split system, packaged unit or heat pump
• Size (tonnage) based on your home’s load calculation
• Efficiency rating (SEER2 for cooling, AFUE or HSPF2 for heating)
• Single-stage, two-stage or variable-speed equipment
• Ductwork condition and any repairs or modifications needed
• Electrical, drain, pad, curb or attic access work
• Permits and code requirements where your home is located

We do not publish one flat price because every home is different, and we will not guess at a number that changes later. Instead, you get a written estimate that lists exactly what is included.

SEER2 and refrigerant changes

New central air conditioners installed in Texas must meet the federal Southeast region minimum of 14.3 SEER2 for split systems. New equipment also uses the newer A2L refrigerants, such as R-454B and R-32, as the industry moves away from R-410A. We will explain what this means for your options and why higher SEER2 can be worth it in a city with long, hot summers.

Ask about current offers. Financing is available for qualified homeowners, so HVAC system replacement does not have to wait for the perfect month. We will explain the options and help you apply.

Planning a larger remodel? Our sister company, AMG Contractors, is a general contractor that handles design-build renovations. We can coordinate your new HVAC system with the rest of the project.

When we replace your system, you get a 1-year labor warranty from Modern Air Systems. New equipment also carries the manufacturer’s parts warranty, typically 10 years when the equipment is registered, subject to the manufacturer’s terms. We help you register your equipment so that coverage is in place.

1. We protect your floors and work area before removing the old equipment.
2. The old refrigerant is recovered by EPA-certified technicians, and old equipment is hauled away.
3. New equipment is set, leveled and connected, with a new or cleaned line set and drain where needed.
4. We pull a vacuum, charge the system to the manufacturer’s specification and check airflow.
5. We test heating and cooling, set up your thermostat and walk you through the new system.

Most straightforward change-outs are completed in one day. Jobs that include ductwork changes, a packaged unit on a roof or a switch from a furnace to a heat pump can take longer, and we tell you the schedule up front.

We started Modern Air Systems because we kept seeing homeowners pay for poor installations, sometimes two or three times over. We would rather do it right once.

• Family-owned and run by Andy Garza, with three generations of HVAC experience in San Antonio
• Licensed and insured, Texas license TACLB27872E
• An honest, repair-first opinion before we recommend HVAC system replacement
• Written, upfront pricing before any work starts
• The same high standard our sister company, AMG Contractors, applies to its construction work

There is no single right system for every house. During an HVAC system replacement, we compare the options that fit your home, your budget and how long you plan to stay.

AC and gas furnace

The most common setup in San Antonio pairs a central air conditioner with a gas furnace. It is a good fit when you already have gas service and want strong heat on the few cold nights each winter.

Heat pump and air handler

A heat pump cools in summer and heats in winter with the same outdoor unit. Many homeowners choose a heat pump during HVAC system replacement because South Texas winters are mild. See our heat pump services for more detail.

Packaged unit

A packaged unit keeps everything in one cabinet outside or on the roof. It is common in older homes, homes without attic space and light commercial buildings. We also handle light commercial HVAC replacements.

Single-stage, two-stage and variable-speed

Single-stage equipment runs at full power or not at all. Two-stage and variable-speed systems run longer at lower speeds, which removes more humidity and keeps temperatures more even. We explain the difference in plain language so you can choose what fits.

• Clear a path to the outdoor unit, indoor unit and attic access
• Move cars out of the driveway if the crew needs space for equipment
• Keep pets in a separate room during the work
• Have your thermostat preferences and Wi-Fi details ready if you are upgrading your thermostat
• Tell us about any rooms that never feel comfortable so we can check airflow

A new system can only perform as well as the ducts that carry the air. Leaky, crushed or undersized ducts in a hot San Antonio attic waste cool air before it reaches your rooms. During every HVAC system replacement, we check the supply and return connections and recommend ductwork repair only when it is needed.

If your system is young and the repair is small, repair it. If your system is older, needs a costly part such as a compressor or coil, or keeps breaking down, HVAC system replacement usually costs less over time. When another company has already told you to replace, our HVAC second opinion gives you an honest check first. You can also verify our Texas license with the Texas Department of Licensing and Regulation before you hire us.