Furnace Repair & Replacement in South Fulton
When a furnace quits, it's usually one small part: a dirty flame sensor, a cracked igniter, a limit switch tripped by a clogged filter. We find it, fix it and test a full heating cycle across South Fulton and nearby towns.
No heat tonight?
Until it is fixed: Don't keep pressing reset or flipping the furnace switch. Repeated restarts can hide a safety fault.
How many years do furnaces usually last?
According to an NAHB study furnaces last around 15-18 years. ENERGY STAR treats one over 15 years as a candidate for replacement. In South Fulton the age is less about how long it has been running and more about how it has been running. Around 36 nights a year drop to 32F or below. The ASHRAE 99% heating design temperature is 26.4F meaning the furnace will sit doing nothing for months and then work very hard during short cold periods. An attic unit also bakes every summer. Much of the city was built in the 2000s, so plenty of original furnaces are now 15-18 years old. In Old National the homes are older and most will be heated with gas.
What a furnace repair visit covers
No heat is why you called. With the panels off, our tech also checks the parts around the fault so the repair holds.
Gas furnace burners, front panel off
Ignition sequence test
We watch the inducer start, the pressure switch close, the igniter glow and the burners light, in that order.
Flame sensor and burners
A dirty flame sensor shuts the gas off seconds after lighting. We clean or replace it and look at the flames.
Heat exchanger inspection
We look for cracks and rust-through. A cracked heat exchanger is the finding that often turns a repair into a replacement.
Filter, blower and limit
A clogged filter overheats the furnace until the limit switch trips. We check the filter, blower wheel and motor.
One full heating cycle
Burners stay lit, the blower runs, warm air reaches the registers and the cycle shuts off cleanly.
Gas and venting check
Gas connections at the furnace, the flue pipe, and on high-efficiency units the condensate trap and drain.
Gas furnace or electric strip heat: which is yours?
A gas furnace has a gas pipe, a flue pipe and burners you can hear light. No flame and no flue usually means electric strips, which is a different repair.
| What to check | Gas furnace | Electric furnace with strip heat |
|---|---|---|
| What it is | Burners heat a heat exchanger; the blower moves the air. | Resistance coils heat the air directly, no flame at all. |
| Where it sits | Attic, closet, crawlspace or basement, with a flue pipe to outside. | An air handler in the attic or a closet. |
| Usually found in | Most owner-occupied homes, paired with a split AC. | All-electric homes, including many South Fulton rentals. |
| What failure looks like | Burners light and then shut off, or cold air blows. | Lukewarm air, or the heat strips keep tripping their breaker. |
| What the repair needs | Flame sensor, igniter, inducer or pressure switch, plus a gas check. | A heating element, sequencer or limit switch, tested under load. |
Why is my furnace blowing cold air but not heating my house?
- Air from the vents starts warm, then turns cold after a few minutes.
- You hear the inducer hum and a click, but the burners never light.
- The thermostat fan is set to On, so air blows between heating cycles.
- Burners light and shut off over and over, a few minutes apart.
- Water pooling around the base of a high-efficiency furnace.
Two or more of these? Swap the filter, check the thermostat, then call us.
Dirty flame sensor beside the burners
Furnace questions we hear in South Fulton
We hear these on most furnace calls in South Fulton. Don't see yours? Call, or send the form.
Gas furnaces
What are the most common complaints about high-efficiency furnaces?
Most trace back to how they are built. A 90%-plus furnace is a condensing unit with PVC vent pipes and a condensate drain, so a clogged trap or a blocked vent can shut it down on a cold morning. Older homes may need new venting run for one.
Is it legal to replace your own furnace in South Fulton?
Possibly. The City of South Fulton lets homeowners doing their own work apply for the permit, and replacements are inspected. In Georgia gas piping after the meter counts as conditioned air work. Most people will choose to have it done.
Electric strip heat
Can I replace just my furnace?
Usually, yes. The tech checks that the existing AC coil fits the new cabinet, the blower suits the AC, and the venting and gas line work. The gas side stays the same: Atlanta Gas Light pipes it and a marketer bills it.
What is the most common part to fail on a furnace?
On gas furnaces, flame sensors and hot surface igniters are among the most common, followed by inducer motors and pressure switches. On electric furnaces it is usually a burned heating element or a sequencer. Each one stops the heat outright.
When it breaks
Is a 25 year old furnace safe?
Age alone doesn't make it unsafe; condition does. At 25, have the heat exchanger and flue checked for cracks, and keep carbon monoxide alarms working. If one sounds or you smell gas, leave without touching switches, then call 911 or the gas company from outside.
Where is the furnace reset button?
Many furnaces have no single reset button; some have one on the blower motor or a rollout switch near the burners. Press it once, no more. Check the filter and the furnace switch, then call us, 7am to 7pm, any day.
No heat? Check the filter, then call us.
Tell us what the furnace is doing, gas or electric, roughly how old it is, and where it sits: attic, closet, crawlspace or basement. That tells us what parts to bring.
(470) 912-2502Open every day, 7am to 7pm