Lennox Furnace Repair Nationwide | Dalton Heating & Air Alpharetta

Lennox Furnace Repair in Alpharetta: What to Know First

Lennox furnace repair in Alpharetta typically runs $150 – $700 depending on the part, and most jobs are completed in a single visit. Dalton Heating & Air Alpharetta is an independent Lennox service provider, which means we carry the common parts on the truck, put the price in writing before any work starts, and back every repair with a full-year written guarantee. If your Lennox is short-cycling, throwing an error code, or not firing at all, this page tells you what is actually wrong, what it costs, and who is showing up. Call (229) 537-2086 for a free estimate – we answer live, 24/7.

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Key Takeaways:

• Most Lennox furnace repairs in Alpharetta run $150 – $700, with the price in writing before we touch a single part.
• We service every Lennox furnace line common to north Fulton and Forsyth county homes, including the G20, G26, G40, G50, G60, EL, ML, and SLP series.
• Every repair carries the 365-Day Done Right Promise: if the repair fails inside a year, we return at no charge. That is not an upgrade – it’s included.
• Calls are answered by a live person, not a voicemail queue. Day or night.

How Lennox Products Fail – and How We Fix Them

Lennox builds a solid furnace, but every line has its known weak spots. After years of service calls across Alpharetta – from Windward to downtown – Marco Benitez and our techs can usually diagnose the issue over the phone before we roll the truck. Here is what we see most often on Lennox units in this area:

• G26 and G40 series – ignition control board failures. These mid-1990s to mid-2000s units use an integrated control board that tends to develop solder-joint cracks after enough heating-season cycles. The symptom is usually a furnace that tries to fire, then shuts off with no error code, or a board that will not send voltage to the hot-surface ignitor. We replace the board with OEM when it is still available, and a quality aftermarket board when it is not – both carry the same one-year written guarantee.
• G50 and G60 series – cracked heat exchangers at the crimp. The G50 and G60 are known for stress cracking where the clamshell halves are crimped together, especially in the third and fourth cell from the burner. A cracked heat exchanger is not a patch job – it is a carbon monoxide hazard. We scope the exchanger with a camera, show you the photos, and walk through repair-versus-replace numbers honestly. Sometimes the right answer is a new furnace, and we will tell you that plainly.
• EL and ML series – pressure switch nuisance trips. The EL195 and ML195 are common in Alpharetta townhomes and newer single-family builds. They are efficient, but the pressure switch circuit is sensitive to condensate drainage issues. A clogged trap or a sagging drain line that holds water will trip the switch intermittently – usually on cold, damp mornings. The fix is often as simple as clearing the drain and re-leveling the line, but a good tech checks the venting and inducer first so the switch does not just trip again next week.
• SLP98 and higher-end modulating units – communicating thermostat signal loss. The SLP98 uses Lennox’s proprietary communicating protocol to talk to the iComfort thermostat. If the wiring is not shielded, or if it was spliced with wire nuts instead of terminal blocks, the signal drops and the furnace either locks out or runs at a fixed low-fire rate. Alpharetta homes with past renovation work are the usual culprits. We restore the wiring by the book, re-commission the thermostat, and verify modulation across all stages before we leave.
• G20 and older units – pilot and thermocouple failures. There are still G20 and other standing-pilot Lennox furnaces in older Alpharetta homes built before the mid-90s. The pilot drops out because the thermocouple has worn thin or the pilot orifice is clogged with combustion dust. Parts for these old workhorses are getting scarce, but we keep common thermocouples and pilot assemblies on the truck. If the heat exchanger is still solid, an old G20 can make it another few winters – and we will tell you exactly when it is no longer worth putting money into.

Our Lennox Furnace Repair Process

Every Lennox job follows the same sequence, whether we are changing an ignitor in a G26 or re-commissioning an SLP98’s modulating gas valve. The Garrison Code applies to every step – no exceptions, no shortcuts.

1. 1
   Call and diagnosis conversation. You describe the symptom. Marco or a tech asks pointed questions – what does it do when it tries to start, what is the error code, when did it first show up. We often know the problem before we arrive.
2. 2
   Arrival and written diagnostic. We show up inside the stated window, in uniform, and inspect the furnace. The diagnostic fee is disclosed on the phone before we ever schedule the call, and the repair price is put in writing before any work begins.
3. 3
   Parts decision – OEM versus aftermarket. For safety components, heat exchangers, and gas valves, we use OEM Lennox parts whenever they are available. For universal components – ignitors, flame sensors, pressure switches – a high-quality aftermarket part is often half the price with equal reliability. We explain the trade-off in plain language and let you decide. The written price reflects that decision.
4. 4
   The repair. We replace the failed part, clean what should be clean, check gas pressure and temperature rise, and verify the unit cycles properly. We do not leave the site until the furnace fires and runs through a full heating sequence.
5. 5
   Test and documentation. We run the furnace through at least three full cycles, confirm no error codes, and hand you a written summary of what failed, what was installed, and what the guarantee covers.
6. 6
   Cleanup and departure. We leave the mechanical room cleaner than we found it, walk you through what we did, and answer any question. The written guarantee is in your hand before we pull out of the driveway.

What Lennox Furnace Repair Costs in Alpharetta

Most Lennox furnace repairs in Alpharetta land between $150 – $700 depending on the part and the furnace series. Here is what we see in this market:

• Flame sensor cleaning or replacement: $150 – $250. This is the most common no-heat fix we make on gas furnaces in Alpharetta.
• Hot-surface ignitor replacement: $200 – $375. G26, G40, G50, and G60 units use ignitors that crack after enough seasons. The part itself is modest; the labor to access it and verify the draft is the rest.
• Pressure switch replacement and drain clearing: $225 – $400. Common on EL and ML series units with condensate issues.
• Inducer motor replacement: $450 – $700. The inducer motor pulls combustion air through the heat exchanger and vents it out. When it gets noisy or stops, the furnace locks out.
• Control board replacement: $350 – $600. G26 and G40 board failures are common, and OEM boards are getting expensive as Lennox phases them out.
• Heat exchanger replacement: $800 – $1,600. On a G50 or G60 with a cracked exchanger, this is usually the moment we have the repair-versus-replace conversation. If the unit is over 15 years old, a new furnace often makes more sense than a $1,200 repair on a heat exchanger that is already past its service life.

The price you are quoted is the price you pay. No surprises at the door. Call (229) 537-2086 and tell us what the furnace is doing – we will give you a straight answer and a free estimate.

Why Alpharetta Homeowners Call Dalton Heating & Air Alpharetta for Lennox Work

Alpharetta homeowners have been burned by no-shows and changed prices. We speak to that directly: the price is in writing before we touch a wrench, on every job, without exception. And the repair is guaranteed in writing for a full year – the 365-Day Done Right Promise. If it fails, we return at no charge. That is not a promo. It is how we have operated since 2003, as a Garrison Partners company bound to The Garrison Standard.

Our techs are factory-trained on Lennox and the other major residential brands – Carrier, Trane, Rheem, Goodman, York, Daikin, Bryant, and American Standard. That matters when you own a Lennox furnace and the board or gas valve behaves differently than generic universal parts expect. We know these units by their failure patterns, not just their model numbers. And if your home runs a Carrier or Trane system alongside the Lennox furnace, the same crew can handle it all in one visit.

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