Expert Heating Diagnosis and Repair From a Family-Owned Contractor
When your furnace stops working or starts showing warning signs, you need a trusted contractor who can diagnose the problem quickly and get your home warm again. Harmon Heating & Cooling has over 35 years of experience repairing furnaces for homeowners across Fishers and nearby areas. Our skilled technicians work with all major brands, provide upfront quotes, and keep your family comfortable without surprises.
We understand how stressful a furnace breakdown can be — especially when it's cold outside. Whether your furnace isn't igniting, is cycling on and off too frequently, or isn't heating evenly, we have the expertise to solve it. Every furnace repair starts with a thorough inspection. Our technicians identify the root cause and present your options clearly so you can make an informed decision.
Considering a new system instead of a repair? Explore furnace installation if replacement makes sense, or protect your system with a maintenance plan.
Thorough Diagnostics
35+ Years of Experience
Honest, Upfront Quotes
Armstrong Air Certified
Local to Fishers
Catching any of these early usually means a smaller repair bill — and no winter nights without heat.
If your furnace doesn't ignite or shuts off unexpectedly, the culprit is often a faulty igniter, a clogged filter, or a thermostat issue. Ignition problems are common in older furnaces — ignition repair is usually straightforward.
Some rooms are cold while others are warm, or the furnace runs but barely heats. This points to a clogged filter, cracked heat exchanger, or ductwork leak. We'll locate the blockage or damage and restore full heating power to every room.
Strange smells — especially a burning odor when the furnace first runs — can signal a dirty filter or electrical issue. Loud banging, rattling, or grinding noises suggest failing bearings, loose ductwork, or a cracked heat exchanger.
If your utility costs spike while your heating habits stay the same, your furnace is working harder than it should. Leaking seals, dirty burners, and worn blowers all waste fuel. A repair often pays for itself in energy savings within weeks.
Your furnace runs for just a few minutes, then stops, then starts again. This erratic cycling stresses the system and usually points to a thermostat miscalibration, clogged filter, or airflow obstruction. Addressing it early prevents larger repairs later.
A CO alarm near your furnace is a critical warning. Do not ignore it. Modern furnaces have safety shutoffs, but a faulty heat exchanger can leak CO. We will inspect immediately.
Five steps from your first call to a system you've watched us test before we leave.
Contact us by phone or online. Tell us what you're noticing — no heat, strange smells, unusual sounds. You choose the appointment window that works for your schedule, we confirm as soon as we can, and we arrive on time, fully equipped with diagnostic tools and clear communication about what to expect.
Our technician inspects your furnace top to bottom — the igniter, burners, heat exchanger, blower motor, thermostat, ductwork, and filter. We test ignition, flame, and electrical circuits, run safety checks including carbon monoxide, measure heating output and efficiency, and document our findings with photos when relevant.
We walk you through what we found and what it means for your comfort and safety, in plain language. You get a written estimate, an explanation of repair vs. replacement trade-offs, a timeline, warranty details on parts and labor, and financing information if you need it. We don't start work until you approve.
Once you approve, we order parts if needed and complete the repair efficiently using quality parts and manufacturer specifications. We run a full system test under load to verify performance, re-check carbon monoxide and safety, and leave the system cleaned with filters replaced.
We explain how to maintain your furnace to avoid future breakdowns — filter changes and basic maintenance — and recommend upcoming service. We offer maintenance-plan enrollment to prevent future repairs, and you can call us with questions after we leave.
These are the failures we diagnose and repair most often on residential furnace systems.
A faulty igniter is one of the most common furnace failures. If your furnace clicks but doesn't light, or the pilot won't stay lit, the igniter is likely the culprit. We replace it with a quality part and test the full ignition cycle, typically restoring immediate heat.
If the furnace heats but no warm air comes out of your vents, the blower motor may be failing. A weak or dead motor reduces airflow and heating effectiveness. We repair or replace the motor and verify air distribution to every room.
The heat exchanger is the furnace's core — it transfers heat from the flame to the air. Cracks or corrosion are serious and can leak carbon monoxide. We inspect for damage and advise repair or replacement based on severity and your furnace's age.
If your furnace won't respond to thermostat changes, or cycles erratically, a faulty thermostat is often to blame. We test and repair or replace it, ensuring your heating commands trigger immediate response.
Leaks in ducts waste heated air before it reaches living spaces, forcing your furnace to work harder. We seal leaks and repair damaged sections, restoring efficiency and comfort throughout your home.
Modern furnaces have multiple safety switches and electronic controls. If a control board fails or a safety switch trips, the furnace shuts down. We diagnose the failure and replace components to restore operation safely.
A clogged filter reduces airflow and forces your furnace to work harder. We replace filters and, if you're interested, upgrade to a high-efficiency filtration system that traps more dust, pollen, and allergens.
Over time, burners accumulate dust and debris, which weakens the flame and reduces heat. We clean burners and adjust fuel-to-air ratios for optimal combustion efficiency and heating output.
Furnace problems are easier to prevent than to fix. Protect your heating system with our maintenance plan. Annual inspections and seasonal tune-ups catch issues early, keep your furnace running efficiently, and help you avoid costly emergency repairs when it's freezing outside.
A new HVAC system is a real investment, and Harmon Heating & Cooling works with Service Finance to help make that investment manageable. Whether you're replacing an aging furnace before winter or upgrading to a more efficient central AC system, financing options are available so an unexpected repair or planned upgrade doesn't have to wait.
Our team can walk you through financing options through Service Finance at the time of your estimate, so you know what to expect before any work begins.
Contact Us to ApplyDon't wait on a failing furnace or AC — get your system installed today and spread the cost into manageable monthly payments.
Flexible terms keep payments predictable, so a new system fits your budget instead of draining your savings all at once.
Financing makes it easier to step up to a more efficient Armstrong system that lowers your energy bills month after month.
We repair heating systems across Central Indiana. Fishers is our home base and gets the fastest response times, with Westfield just west, Noblesville north, Fortville east, Pendleton to the southeast, and Carmel to the south.
Don't see your city listed? Harmon Heating & Cooling serves additional communities throughout Central Indiana beyond our primary service area — reach out and we'll let you know if we cover your address.
Considering a new furnace? These are the paths we can walk you through, and the same family team handles all of them.
A broken furnace is stressful, but quick professional repair gets your home warm and keeps your family comfortable. Harmon Heating & Cooling has the expertise, experience, and honesty to diagnose your furnace problem and fix it right — locally owned, family-operated, and committed to upfront pricing. Trust the contractor who has served Indiana homes for over 35 years.
Call 317-588-8303 today and we’ll get you warm again. Flexible financing is available through Service Finance, and regular maintenance keeps problems from becoming emergencies.
