Lennox HVAC Service Nationwide

Why San Antonio Homeowners Choose Lennox HVAC

We’re a San Antonio Lennox service provider, and we repair, maintain, and install Lennox furnaces, air conditioners, heat pumps, and mini-splits across the entire metro area. What makes our Lennox work different is simple: our techs see these systems daily, from 20-year-old G26 furnaces to current EL296V modulating units, and we carry the diagnostic protocols and torque specs for Lennox-specific boards, inducers, and modulating gas valves. That means we fix root causes without factory authorization, because we’ve spent years learning exactly how Lennox equipment fails in San Antonio’s brutal heat and humidity. Andre Fuller built Halden Heating and Air San Antonio on one rule he’s never bent: tell the customer the price before anyone opens a toolbox. If your Lennox system is acting up, call (903) 623-6784 and you’ll get a written price before any work begins.

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Why Trust Halden Heating and Air San Antonio for Your Lennox HVAC?

Lennox makes sophisticated equipment. The iComfort S30 thermostat communicates with the outdoor unit over a proprietary protocol. SureLight control boards have firmware that aftermarket replacements often can’t match. Modulating gas valves need specific torque settings or they’ll leak or misread flame signal. Our techs know these systems because we work on them constantly, not occasionally. Andre got his start at Los Angeles Trade-Technical College and has spent more than 25 years diagnosing HVAC systems, including the tricky intermittent no-cools that three other techs missed. He and the crew have kept homes comfortable across San Antonio and Universal City Lennox service areas for years, including plenty of calls near the Pearl District where older buildings and Texas summers test every system. When we roll up to a Lennox repair in San Antonio, we bring the right board, the right torque spec, and the right diagnostic approach the first time.

One more thing: we are not affiliated with or authorized by Lennox. We’re an independent Lennox service provider, which means we answer to you, not a manufacturer scorecard. Every repair includes a written guarantee. If it fails within the coverage window, we come back at no charge. That’s the 365-Day Done Right Promise, and it applies to every Lennox job we complete.

Common Lennox HVAC Problems We Fix in San Antonio

These are the specific failure modes we see on Lennox equipment in San Antonio, week after week. If any of these sound familiar, call us at (903) 623-6784.

• SureLight control board failures from voltage spikes. San Antonio gets frequent lightning storms, and Lennox SureLight boards are sensitive to voltage irregularities. A power surge can knock out the ignition sequence entirely, leaving you with a furnace that won’t light. We test the board, check the flame sensor and rollout switches, and replace with genuine Lennox OEM when needed. Aftermarket boards often lack the correct ignition timing for SureLight, so we don’t use them on this component.
• iComfort S30 communication faults causing intermittent cooling. On Lennox XC25 and other iComfort systems, the thermostat and outdoor unit talk constantly over a communicating protocol. When that communication drops, you get short-cycling, no cooling, or a system that runs but won’t satisfy the setpoint. We’ve traced this to failed outdoor control boards, damaged low-voltage wiring, and occasionally a bad thermostat. It’s a diagnosis that requires patience and the right test equipment.
• Evaporator coil leaks on Merit Series ML14XC1 units (2015 – 2020). These coils are prone to formicary corrosion, especially in San Antonio’s high humidity. You’ll notice low refrigerant, weak cooling, and eventually a frozen coil. We pressure-test with nitrogen, locate the leak, and give you a straight answer on whether a coil replacement makes sense versus a new system.
• Inducer motor failures on older G26 and G40 furnaces. These furnaces are workhorses, but the inducer motor is often the first thing to go. The telltale sign is a rumbling or grinding noise before the burners even light. We check the motor’s amp draw and bearing play, and if it’s on its way out, we replace it with an OEM or verified-compatible motor before it takes the pressure switch with it.
• Water leaks from MS8 mini-split indoor units. San Antonio’s humidity means mini-splits produce a lot of condensate. When the drain line clogs or the unit isn’t perfectly level, water backs up and drips inside. We clean the drain, check the pitch, and make sure the condensate pump (if installed) is doing its job. It’s a common call in summer, and usually a quick fix.

Lennox Parts & Our Repair-vs-Replace Approach

For critical Lennox components like control boards, gas valves, and inverters, we use genuine Lennox OEM parts. Here’s why: aftermarket boards often lack the exact firmware needed for iComfort communication, and a gas valve that doesn’t match the original spec can cause flame signal errors or unsafe operation. For non-critical items like capacitors and contactors, quality aftermarket parts are fine, and they save you money without any performance or safety trade-off. We keep common Lennox parts stocked locally so we aren’t waiting on a shipment when your AC is down in July.

When it comes to repair versus replace, we give you the honest math. If a Lennox compressor is grounded, or a heat exchanger is cracked beyond warranty, repair rarely makes sense. We’ll walk you through the numbers, show you what a new system costs, and let you decide. No pressure, no games. Call (903) 623-6784 and we’ll tell you what we’d do if it were our house.

Our Lennox Service Process – Step by Step

Here’s exactly what happens when you book a Lennox service call with Halden Heating and Air San Antonio.

1. 1
   Diagnosis. We test the system with the right tools: a communicating thermostat diagnostic for iComfort, combustion analysis for furnaces, and nitrogen pressure tests for suspected coil leaks. You get a written diagnosis with the exact part and the exact price before we touch a wrench.
2. 2
   Repair or Installation. Once you approve the written price, we complete the work. For Lennox-specific components, we use OEM parts. Every torque spec is followed, every board is paired correctly, and every gas valve is checked for proper inlet and outlet pressure.
3. 3
   System Test. We verify the system performs to spec. On an XC25, that means confirming proper communication between the thermostat and outdoor unit and a 25-degree temperature drop across the coil. On a furnace, that means verifying ignition, flame signal, and inducer operation across multiple cycles.
4. 4
   Written Warranty. Every Lennox repair includes a written guarantee. If it fails within the coverage window, we come back at no charge. That’s the 365-Day Done Right Promise, and it’s included automatically, not sold as an add-on.

Lennox Products We Service & Install in San Antonio

We service and install the full range of Lennox residential equipment, and we know the quirks of each line. The Elite Series (EL296V furnace, EL18XCV air conditioner) is common in newer homes in Lennox HVAC in Timberwood Park, TX and throughout the area and gives us communicating-system diagnostics. The Merit Series (ML14XC1, ML180) is the builder-grade workhorse we see across north and west side tract homes. The Dave Lennox Signature Collection (SL280, XC25) is the premium equipment we service in Alamo Heights and Olmos Park, where older homes often push these systems to their limits. And we install and service Lennox mini-splits (MS8, MPB) for additions, garages, and homes without ductwork.

We Also Service These Brands

Lennox is a brand we know deeply, but we’re a multi-brand shop. Our techs service Carrier and Trane systems the same way: with OEM-grade diagnosis, written pricing, and the same 365-Day Done Right Promise. If you have mixed-brand equipment in your San Antonio home, one call handles all of it.

FAQs – Lennox HVAC Service in San Antonio

Book Your Lennox Service in San Antonio, TX

Straight answer, written price, no runaround. That’s how every Lennox service call works with Halden Heating and Air San Antonio. Call (903) 623-6784 for a free estimate, and you’ll get a live person on the line, a real diagnosis, and a written price before any work starts.

Written by Andre Fuller, Owner at Halden Heating and Air San Antonio, serving San Antonio since 2004.