Light Commercial HVAC in San Antonio

Commercial HVAC covers the heating and cooling equipment in businesses, offices, restaurants, clinics and other non-residential buildings, most often rooftop units and packaged units. Modern Air Systems repairs, maintains and replaces light commercial HVAC equipment across San Antonio, with written pricing before work starts and records for every unit we service.

• Rooftop unit (RTU) repair and diagnostics
• Packaged unit replacement on roofs and slabs
• Split system service for offices, retail and restaurants
• Preventive maintenance agreements for one or many units
• Thermostat and controls upgrades
• Ductwork repair and airflow balancing
• New construction and tenant finish-out HVAC with contractors and builders

We focus on light commercial equipment, the rooftop and packaged units common on strip centers, offices, churches, clinics, small warehouses and restaurants.

Rooftop units hold the compressor, coils, blower and often gas heat in one cabinet. Because they sit in direct sun and weather year-round, the most common commercial HVAC calls we see in San Antonio are:

• Failed capacitors, contactors and fan motors
• Dirty condenser coils that cause high head pressure on hot days
• Clogged condensate drains and overflowing drain pans
• Slipping or worn belts on belt-drive blowers
• Economizer dampers stuck open or closed
• Refrigerant leaks and low charge
• Gas heat ignition and flame sensor problems in winter

We diagnose the problem, explain the fix and give you a written price before work starts.

Most commercial HVAC failures start small. A preventive maintenance agreement keeps your units on a schedule so we catch problems early. A typical rooftop unit maintenance visit includes:

Many buildings need filter changes and inspections quarterly, with a full cooling check in spring and a heating check in fall. We set the schedule based on your equipment, occupancy and how dusty the site is, and we keep a record for every unit.

When a rooftop unit reaches the end of its life, we help you plan the replacement around your business hours. That includes matching the existing curb or using an adapter curb, coordinating crane lifts where needed, connecting gas, electrical and ductwork, and pulling permits where your city requires them.

We give you options, not a single take-it-or-leave-it price, and we explain the trade-offs between repairing an older unit and replacing it.

• Small business owners and retail tenants
• Property managers and landlords with commercial or mixed-use buildings
• General contractors and builders on new construction and finish-outs
• Restaurants, clinics, offices, churches and small industrial spaces

For public or institutional buildings, we work through your facility team and follow your procurement and access requirements.

• Licensed and insured, Texas license TACLB27872E
• Family-owned, with three generations of HVAC experience in San Antonio
• Written, upfront pricing before work starts
• Clear records for every unit we maintain
• An honest opinion on repair versus replacement

Rooftop units sit in full sun on hot roofs, where surface temperatures climb far above the air temperature. That heat, plus dust from parking lots and roads, puts extra strain on commercial HVAC equipment. The most common results are high head pressure, failed fan motors, tripped safeties and compressors that overheat on the hottest afternoons.

Kitchens add heat, grease and humidity that make commercial HVAC work harder. Grease-loaded coils and filters reduce airflow, and dining rooms can feel stuffy even when the system runs nonstop. We set a maintenance schedule that keeps coils, filters and drains clean between busy seasons.

Offices and clinics need steady temperatures for staff and patients. Retail spaces need comfort for customers who will leave if a store feels hot. We help property managers and owners plan commercial HVAC maintenance and replacements around business hours, and we coordinate access with on-site managers.

When a rooftop unit is near the end of its life, a planned replacement costs less disruption than an emergency on a hot day. We look at the age and repair history of each unit, check the curb, duct connections, gas and electrical supply, and give you options. Our HVAC system replacement process applies to packaged units too, and our property manager services cover multi-unit portfolios.

Commercial HVAC work in Texas must be performed under a license from the Texas Department of Licensing and Regulation. You can verify our license, TACLB27872E, before you hire us.