Lennox Furnace Repair Nationwide

Lennox Furnace Repair in San Francisco: What to Know First

Lennox furnace repair in San Francisco typically runs $175 – $825, and most jobs are completed in a single visit because we stock common Lennox parts on our trucks. We’re an independent Lennox service provider, which means we repair every Lennox line without being tied to factory pricing or corporate service schedules. A live person answers our phone 24/7, and every repair starts with a written price before any work begins.

Call (559) 245-8807

If you own a Lennox furnace in San Francisco and it’s making noise, short-cycling, or blowing cold air, this page tells you exactly what’s going wrong, what it costs to fix, and how we work. Call (559) 245-8807 and you’ll get Devin Marlowe’s team, not a call center.

How Lennox Products Fail – and How We Fix Them

Lennox builds solid furnaces, but after 20-plus years of hands-on work across San Francisco, we’ve seen the same failure patterns repeat. Here are the five most common Lennox furnace issues we repair, by model line where it matters.

• Elite Series (EL296E, EL195E): Ignitor failure. The silicon nitride hot-surface ignitors Lennox uses are efficient but brittle. They crack after years of thermal cycling, and when they do, the furnace cycles the blower but never ignites. We replace them with OEM Lennox ignitors or a nitride aftermarket equivalent rated for the same voltage. Parts and labor typically land between $175 and $340.
• Merit Series (ML193, ML180): Pressure switch faults. These mid-efficiency furnaces use a single-stage inducer that pulls combustion air through a small port. In San Francisco’s damp, foggy climate, that port corrodes faster than it does inland. The furnace throws a pressure switch code and locks out. We clean or replace the port, test the switch with a manometer, and confirm the furnace drafts properly before we leave.
• Signature Series (SL297NV, SLP98): Variable-speed blower motor failures. The modulating Signature line uses ECM motors that are smooth and quiet until they burn out a control module. Homeowners in the Richmond District and Pacific Heights call us about a furnace that hums but won’t spin the blower. The fix is usually a new module or motor assembly, which runs $380 – $825 depending on the motor class.
• Legacy G-series (G61, G71): Heat exchanger rust-through in basements and garages. Older Lennox models with tubular heat exchangers develop pinhole cracks over time, especially in San Francisco homes where salt air and high humidity accelerate corrosion. If our combustion analyzer shows elevated CO or we see rust trails on the exchanger, we shut the furnace down, show you the crack with a borescope, and quote a heat exchanger replacement or a new system. We never patch a cracked exchanger.
• EL195E and EL296V: Gas valve sticking. Lennox gas valves from the mid-2010s are prone to internal diaphragm wear, causing intermittent no-heat calls. The furnace lights sometimes, then drops out. We verify gas pressure at the manifold, confirm the valve isn’t getting correct voltage, and replace the valve when it’s failed. This repair usually lands between $310 and $540.

Our Lennox Furnace Repair Process

When you call about a Lennox furnace that won’t heat, here’s how the job goes, step by step.

1. 1
   You call and talk to a person. No phone tree. We ask what the furnace is doing, what the thermostat reads, and whether you smell gas or hear anything unusual. If we suspect a gas leak, we tell you to leave the home and call PG&E first.
2. 2
   We show up when we say we will. Our technician arrives in a Brandt HVAC uniform, with a photo ID badge. Before we knock, you get a text with the tech’s name, photo, and arrival time so you know exactly who’s at the door.
3. 3
   We diagnose before we touch anything. We’ll get the error code from the control board, check gas pressure, test the ignitor, and verify airflow. You get a plain-English explanation of what’s broken and why. No jargon, no mystery.
4. 4
   We hand you a written price. Before any work starts, you see the exact cost in writing. This is a Brandt HVAC rule, not a courtesy. If you decide the repair isn’t worth it, that’s your call and we’ll tell you the honest condition of the furnace either way.
5. 5
   We repair with OEM Lennox parts or quality aftermarket equivalents. For warranty-sensitive components like heat exchangers and gas valves, we use OEM Lennox parts. For wear items like ignitors and flame sensors, we use OEM or tested aftermarket parts that match spec, and we’ll tell you which one is going in and why.
6. 6
   We test, we document, and we guarantee it. Before we leave, we run the furnace through a full heating cycle, verify temperature rise, and check for CO. You get a written report of the repair and a written guarantee. If that repair fails within 365 days, we return at no charge under the 365-Day Done Right Promise. Period.

What Lennox Furnace Repair Costs in San Francisco

Lennox furnace repair in San Francisco spans a range because the job depends on what failed. Here are real numbers for common Lennox repairs, parts and labor included.

What moves the price: the model line, whether the part is OEM, and how much disassembly is required. A Merit Series ignitor swap is a 30-minute job. A Signature Series blower motor replacement takes longer and costs more because the parts are more expensive. Every repair starts with a free estimate and a written price, so you’ll never be surprised by the invoice.

Why San Francisco Homeowners Call Brandt HVAC Co San Francisco for Lennox Work

Most San Francisco homeowners don’t choose an HVAC company because they love furnaces. They choose one because they want to know who’s walking through their front door. So should you. Every Brandt HVAC technician is background-checked, identity-verified under the Threshold Standard, and sent to you by name and photo before arrival. If the person at your door isn’t the person we told you to expect, that visit is on us and we make it right.

We also do the work right the first time. Every Lennox repair carries a written guarantee and the 365-Day Done Right Promise. If the repair fails within a year, we come back free. And because we service Carrier and Trane as well, we can tell you honestly when a Lennox repair is worth the money or when a different system would serve you better. We’re in the business of warm homes, not pushing parts.

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