Gas Furnace Repair
Furnace Repair in Elgin & the Fox Valley
No heat, a furnace that clicks but never lights, or a blower that runs cold? We diagnose and repair every major brand of gas furnace, day or night. You get a clear flat-rate price before we touch a part.
- 24/7 no-heat emergency service
- All brands repaired
- Price approved before work starts
- Licensed, insured and bonded
Signs Your Furnace Needs Repair
Most furnaces give a warning before they quit. Elgin winters run near 0°F at design conditions, and a furnace that is struggling in November will not get better in January. Call us if you notice any of these.
- No heat at all. The thermostat calls, and nothing happens, or the furnace starts and shuts down within seconds.
- Blower runs but the air is cold. Usually an ignition or flame-sensing failure. The furnace is trying, but it can’t prove a flame.
- Short cycling. It lights, runs two or three minutes, shuts off, then repeats. Often overheating from a plugged filter or a failing limit switch.
- Clicking without ignition. Repeated clicks are the igniter or spark trying and failing. Three failed tries usually locks the furnace out for an hour.
- A flashing status light. The LED behind the lower door blinks an error code. Note the pattern before you reset the power; it tells us where to look.
- Banging, squealing, rattling or grinding. Delayed ignition, a worn blower bearing and a loose inducer wheel each sound different, and none of them fix themselves.
- Rooms that never warm up. The furnace runs constantly and the house still feels cold. Could be a weak blower, a stage stuck low, or a furnace that was never sized right.
- A yellow, lazy or flickering burner flame. Burner flames should be crisp and blue. Yellow means dirty burners or incomplete combustion, and that is a safety concern, not just a comfort one.
- Water around the base. On a 90%+ furnace, a clogged condensate trap or drain will trip the pressure switch and shut the unit down.
- Gas bills climbing with no change in use. A furnace that is running longer to do the same work is telling you something is worn.
Smell gas? Leave the house right away, call 911 from outside, and call your gas utility’s emergency line from outside before calling us.
Carbon monoxide alarm going off? Treat it the same way. Get everyone outside, call 911 or your utility, and do not run the furnace again until it has been inspected.
The Most Common Furnace Failures We See
After enough no-heat calls across Kane, McHenry, DuPage and DeKalb counties, the same handful of parts show up again and again. Here is what fails, how you can tell, and what we do about it.
Most common
Hot surface igniter
The silicon carbide or silicon nitride element that glows to light the burners. It gets brittle with age and cracks, usually on a cold morning. Symptom: the inducer runs, you hear the gas valve click, but nothing lights. We confirm it with a resistance and voltage test, then replace it with the correct igniter for your model, not a universal one that runs too hot.
Quick fix
Flame sensor
A thin metal rod that sits in the flame and tells the control board the burners lit. A film of oxidation makes it read weak, so the board shuts the gas off after a few seconds. Symptom: the furnace lights, runs 3 to 10 seconds, and drops out, three times in a row. We clean it, test the microamp signal, and replace it if the signal is still low.
Airflow related
Pressure switch and inducer motor
The inducer motor pulls combustion air through the heat exchanger and out the vent. The pressure switch proves that it is working before gas is allowed to flow. A cracked inducer wheel, a plugged condensate trap, a blocked vent or a stiff diaphragm will all fail the switch. We check the vent, the trap and the hoses first, because replacing a switch that is doing its job does not fix anything.
Loud failure
Blower motor and capacitor
The blower moves the heated air through your ducts. Capacitors weaken and the motor hums without starting. Bearings wear and the motor squeals or grinds. On ECM and variable-speed blowers, the module can fail separately from the motor. We test the capacitor under load, check amperage against the nameplate, and repair or replace the right piece.
The brain
Control board
The integrated furnace control runs the ignition sequence and every safety check. Boards fail from power surges, a wet basement, or a relay that finally burns. Symptoms range from a dead furnace to a blower that never shuts off. We verify the inputs and outputs before condemning a board, because a bad board is often the last thing wrong, not the first.
Overheating
High limit switch
The limit opens when the heat exchanger gets too hot, usually because airflow is restricted. A clogged filter, closed supply registers, a dirty blower wheel or a collapsed duct will trip it. Replacing the limit without fixing airflow only buys a few weeks. We measure temperature rise and static pressure so the fix lasts.
Not the furnace
Thermostat, wiring and low-voltage faults
Dead batteries, a loose R or W wire, a blown 3-amp fuse on the board, or a float switch on a nearby humidifier or AC coil drain can keep a perfectly good furnace from starting. These are quick to find if you check them in order, and they are some of the cheapest repairs we make.
Cracked heat exchanger? That one is different. A heat exchanger separates combustion gases from the air in your house, and a crack can let carbon monoxide into the airflow. We shut the furnace down, show you what we found, and walk you through furnace replacement.
What to Expect on a Furnace Repair Visit
You should know exactly what is happening at each step. Here is how a repair call with us goes.
1. Booking. Call (847) 224-2420 or book online any time. Tell us what the furnace is doing, and if you saw the status light flash, tell us the pattern. No-heat calls get priority, and we run 24/7 for emergencies.
2. Diagnosis. The technician starts at the thermostat and works toward the burners: power and fuses, the call for heat, the inducer, the pressure switch, the igniter, the gas valve and the flame signal, in the order the furnace itself runs them. We read the fault history on the board, check the filter, and look at the vent and condensate on 90%+ furnaces. On older 80% furnaces we inspect the heat exchanger and draft as well. This takes 30 to 60 minutes on most furnaces.
3. Findings and price. We show you the failed part and explain what caused it, because a failed part usually has a reason. Then you get a flat-rate price for the repair, written, before any work begins. A second, non-urgent issue gets mentioned, not pushed. The repair is quoted flat-rate, and you approve that price before any work.
4. The repair. Our vans carry igniters, flame sensors, capacitors, pressure switches, limits and universal-fit parts for the brands common in Fox Valley basements, so most repairs are finished the same visit. If a specific board or motor has to be ordered, we tell you the lead time and, where it is safe, leave the furnace running until it arrives.
5. Testing. A repair is not done when the part is in. We run a full heat cycle, check the flame signal, measure temperature rise, confirm the safeties open and close, and on condensing furnaces make sure the trap is draining. Then we put the doors back on and leave the area the way we found it.
6. Follow-through. You get an invoice that lists the part, the test readings and any recommendations. If your furnace is at an age where the next repair might not be worth it, we say so plainly and can put together a free written replacement quote with the Nicor Gas discount already figured in.
What Furnace Repair Costs in the Fox Valley
Flat-rate pricing, approved in writing before work starts. No hourly meter running while we look for parts.
Every repair visit starts with a flat diagnostic fee. During office hours (9 a.m. to 5 p.m., Monday through Friday) the service call is $130; weekday evenings after 5 p.m. it is $180, and nights, weekends and holidays are $260. Each includes 30 minutes of travel and 30 minutes of diagnostics, and parts are extra. That covers the trip and the time it takes to find the actual problem. The repair is quoted separately, flat-rate, for you to approve before any work. If you decide not to repair, the diagnostic fee is all you owe, and you keep the written findings.
Most furnace repairs in our area, including igniters, flame sensors, pressure switches, capacitors, inducer motors and control boards, typically land between about $300 and $1,800 parts and labor. Blower motors and complete inducer assemblies sit at the top of that range, and variable-speed blower modules can be higher depending on the brand. A cracked or leaking heat exchanger usually means replacement rather than repair.
| Repair | Typical symptom | Where it falls in the range |
|---|---|---|
| Flame sensor cleaning or replacement | Lights, then shuts off in seconds | Lower end |
| Hot surface igniter | Clicks or glows, never lights | Lower end |
| Run capacitor | Blower hums, won’t start | Lower end |
| Pressure switch | Blinking code before ignition | Lower to middle |
| High limit switch | Short cycling, overheating | Lower to middle |
| Control board | Dead furnace or erratic behavior | Middle to upper |
| Inducer motor assembly | Grinding or no draft | Upper end |
| Blower motor | Squealing, no airflow | Upper end |
| Heat exchanger | CO, rust, flame disturbance | Usually replacement |
Our maintenance plan members get 5% off repairs, priority scheduling during the first cold snap, and one free business-hours service call each year. If the repair is large enough that financing helps, you can prequalify in about 2 minutes with no impact to your credit score.
Repair or Replace? How We Decide
We will fix almost any furnace. The question is whether you should pay to fix this one.
Start with the 50% rule. If the repair costs more than half of what a new furnace would cost, replacement almost always wins, because you are putting a lot of money into equipment that is still old everywhere else. Under that line, age becomes the deciding factor.
- Under 10 years old: repair it. Parts are available, and many are still under the manufacturer’s parts warranty if the furnace was registered.
- 10 to 15 years old: repair the inexpensive things. Weigh a big-ticket blower or board against the furnace’s overall condition and whether it has had other failures recently.
- 15 years or older: get a replacement quote alongside the repair price before you decide. A 15-year-old 80% furnace in Elgin is near the end of its life, and a 97% AFUE replacement with the Nicor Gas discount often costs less than people expect.
- Any age with a cracked heat exchanger: replace. It is a safety issue first and a cost issue second.
- Repeated repairs: two or three service calls in a couple of winters means the furnace is wearing out as a whole, not failing one part at a time.
When replacement is the better call, we give you a free written quote the same visit, and we can usually install within days. Read more on our furnace replacement and furnace installation pages, or see our overall furnace services. Thinking about adding a heat pump and keeping the furnace as backup? That dual-fuel setup is common here, and we cover it under heat pumps.
Why Fox Valley Homeowners Call Rest Assured for Furnace Repair
We are a local Elgin company, not a call center. The person who answers can tell you when a technician will be there.
An Amana gas furnace with an AprilAire air filter, installed by our team.
- Every major brand repaired: Carrier, Bryant, Lennox, Trane, Goodman, Amana, Daikin, Rheem, York, American Standard and more
- Owner Jeff Kerley is EPA 608 Universal and NATE certified in gas heating installation
- Municipally licensed in Elgin, Aurora, Bartlett, Huntley and Streamwood
- BBB of Chicago & Northern Illinois Complaint Free Award, 2024 and 2025
- Housecall Pro Superpro 2024 through 2026, with online booking any time
- Nicor Gas Contractor Circle Installing Member for when replacement makes sense
- Stocked vans, so most repairs are done in one visit
Want to avoid the next breakdown? A fall furnace tune-up catches weak igniters, dirty flame sensors and failing capacitors before the first cold snap.
After the Repair, Keep It Running
Our semi-annual maintenance plan is $240 a year: a fall furnace tune-up and a spring AC or heat pump tune-up, each up to a $130 value, plus one free business-hours service call, priority scheduling and 5% off services. That is up to $390 in services for $240, and it is the single best way to make a furnace last.
If the repair leads to a replacement instead, we take the Nicor Gas instant discount right off your invoice: $225 on a furnace rated 97% AFUE or higher, or $150 at 95% AFUE, and $275 or $200 with a qualifying smart thermostat on the same invoice. See Nicor Gas instant discounts.
Furnace Repair Across the Fox Valley
Based in Elgin, we serve homes throughout Kane, McHenry, DuPage and DeKalb counties.
- Elgin
- South Elgin
- St. Charles
- Aurora
- Bartlett
- Streamwood
- Huntley
- Plato Center
- Sycamore
- Carpentersville
- West Dundee
- East Dundee
- Algonquin
- Gilberts
- Hampshire
- Pingree Grove
- Campton Hills
- Geneva
- Batavia
- Barrington
- Hoffman Estates
- Schaumburg
- Burlington
- Marengo
- Wayne
- Sleepy Hollow
Don’t see your town? Call (847) 224-2420. View all service areas.
Furnace Repair FAQs
Do you offer 24-hour emergency furnace repair in Elgin?
Yes. No-heat calls are answered 24/7 at (847) 224-2420. We serve Elgin and the surrounding Fox Valley towns in Kane, McHenry, DuPage and DeKalb counties.
How much does furnace repair cost in the Fox Valley?
Most common furnace repairs, such as igniters, flame sensors, pressure switches, capacitors, inducer motors and control boards, typically run between about $300 and $1,800 parts and labor. You get a flat-rate price in writing before any work starts.
What is the diagnostic fee?
The diagnostic fee is a flat charge that covers the trip and the time to find the actual problem. The repair is quoted separately, flat-rate, and you approve that price before any work. If you decline, the fee is all you owe.
Why does my furnace turn on and then shut off after a few seconds?
That pattern almost always points to the flame sensor. It has oxidized and can’t prove the flame, so the board shuts the gas off. Cleaning or replacing the sensor is one of the quickest and least expensive furnace repairs.
Why is my furnace clicking but not lighting?
Repeated clicking with no ignition usually means a failed hot surface igniter or spark igniter, or a gas valve that isn’t opening. After three failed tries the furnace locks out for about an hour. We test the igniter and gas valve to confirm which one failed.
My furnace blower is running but the air is cold. What’s wrong?
The furnace is calling for heat but the burners aren’t lighting or staying lit, so the blower moves unheated air. Common causes are a cracked igniter, a dirty flame sensor, a tripped pressure switch or a stuck gas valve. On some furnaces the fan switch was simply set to ON at the thermostat.
What does the blinking light on my furnace mean?
The status LED flashes a fault code, and the legend is printed on the inside of the lower door. Common codes cover pressure switch faults, ignition failure, a tripped limit and a flame sensed out of sequence. Write down the pattern before you reset the power so we can use it.
Can I reset my furnace myself?
You can try once: turn the power switch off for 30 seconds, check that the filter isn’t clogged and the thermostat has batteries, then turn it back on. If it fails again or locks out repeatedly, stop and call. Repeated resets can mask a safety fault.
Do you repair furnaces you didn’t install?
Yes. We repair and maintain all major brands of gas furnaces, including Carrier, Bryant, Lennox, Trane, Goodman, Amana, Daikin, Rheem and York, no matter who installed them.
Is a cracked heat exchanger worth repairing?
Usually not. A cracked heat exchanger can let carbon monoxide into your air, so the furnace is shut down. Unless the furnace is young and the exchanger is covered under warranty, replacement is the safer and more economical answer.
Why does my furnace short cycle?
Short cycling is usually overheating from restricted airflow: a dirty filter, a dirty blower wheel, closed registers or undersized ducts trip the high limit. It can also be an oversized furnace or a failing limit switch. We measure temperature rise and static pressure to find which.
Why is there water around my furnace?
On a high-efficiency condensing furnace, water means the condensate trap, drain line or pump is clogged or failed. On an 80% furnace, water usually comes from the AC coil drain or a humidifier, not the furnace itself. Either way, standing water will eventually shut the furnace down.
How long does a furnace repair take?
Diagnosis takes 30 to 60 minutes on most furnaces, and common repairs are finished the same visit because we stock igniters, flame sensors, capacitors, pressure switches and limits on the van. Special-order boards or motors add a day or two.
Should I repair a 15-year-old furnace?
Small repairs, yes. For a large repair on a furnace 15 years or older, get a replacement quote alongside the repair price. If the repair is more than half the cost of a new furnace, replacement is almost always the better decision.
Does my furnace repair come with a warranty?
Your invoice lists the part we installed and the warranty terms that apply to it. On newer furnaces that were registered, the manufacturer’s parts warranty may cover the part itself, and we’ll check that before you pay for one.
Is the repair cheaper if I’m on the maintenance plan?
Yes. Maintenance plan members get 5% off services, priority scheduling and one free business-hours service call per year, in addition to the two tune-ups.
Should I be worried about carbon monoxide from my furnace?
A properly working furnace vents combustion gases outdoors. A cracked heat exchanger, a blocked vent or a backdrafting flue can change that. Every home with gas appliances should have a working CO alarm on each level, and we test for CO on every repair and tune-up.
No Heat? We’re On It.
Call any time for emergency furnace repair in Elgin and the Fox Valley, or book a repair online and we’ll confirm your arrival window.
Furnace on its last legs? Request a free replacement quote or see financing options.
Discount amounts reflect the 2026 Nicor Gas Energy Efficiency Program for qualifying equipment installed January 1 through December 31, 2026, and are subject to change or cancellation due to funding limits. Rest Assured HVAC LLC is an independent contractor and is not affiliated with or endorsed by Nicor Gas.
