Furnace Won't Start During a Wichita Cold Snap: 6-Step Diagnostic Checklist

It’s 6 a.m., the windchill in Wichita is reading -8°F, and your furnace is dead silent. The thermostat shows 58°F and dropping. You’ve got two kids getting ready for school, a job to get to, and an HVAC company that — if you call right now — quotes you a 4-hour window before a tech can arrive.

Before you make that call, run through this list. About 40% of “dead furnace” calls during a Wichita cold snap turn out to be problems you can fix in ten minutes with the breaker panel and a screwdriver. The other 60% need a tech, but knowing exactly what’s failing helps us bring the right parts on the first visit.

This is the order our techs work through when they arrive at a no-heat call.

1. Confirm the thermostat is actually calling for heat

The most embarrassing fix and also one of the most common. Walk to your thermostat and verify:

• Mode: “Heat” — not “Cool,” “Off,” or “Auto” (Auto can sit on cooling for hours during a warm afternoon and then fail to switch back if the differential isn’t right)
• Setpoint: at least 3°F above current room temperature
• Display: powered, not blank, no low-battery warning
• Fan: “Auto” is normal

If the display is dim, blank, or showing a battery icon, replace the batteries. Most Wichita thermostats use AA or AAA — a fresh set is $4 at any grocery store. Smart thermostats (Nest, Ecobee, Honeywell T-Series) without a C-wire can also lose power in cold weather when the furnace’s pilot trickle current drops; a dead Nest in January is more often a wiring issue than a thermostat failure.

If the thermostat is working but the furnace still won’t run, move on.

2. Check the furnace power switch and breaker

There’s almost always a light-switch-style toggle on the wall near the furnace itself — usually red or marked “Furnace.” Make sure it’s on. Cleaning crews, kids, and curious cats turn this off every January.

Then walk to your electrical panel. The furnace is on a dedicated 15A or 20A breaker, often labeled “Furnace” or “FAU.” If the breaker is in the middle position, push it firmly to OFF, then back to ON.

If the breaker holds, walk back and listen for the furnace to start its sequence — you should hear a small fan (the inducer motor) spin up within 30–60 seconds of the thermostat calling for heat.

If the breaker trips again immediately, stop. A repeating trip indicates a real fault — usually a seized inducer motor, a damaged control board, or a short. Continuing to reset it can damage components or start a fire. Call us.

3. Replace the air filter

A clogged filter starves the furnace of return air, which causes the heat exchanger to overheat, which trips the high-limit safety, which shuts the burners off. The furnace cycles fan-only for a few minutes, then tries again, then shuts down for the day.

Pull your filter out and hold it up to a window. If you can’t clearly see light through it, replace it. In Wichita, plan on 30–60 day filter intervals during heating season — winter dust and pet dander load filters faster than people expect.

If the filter was the issue, the furnace usually needs a 30-minute cooldown before it’ll relight. Set the thermostat to off, wait 30 minutes, then back to heat.

4. Check the condensate line (high-efficiency furnaces only)

If your furnace is a 90%+ AFUE high-efficiency unit — you can tell because it vents through white PVC pipe through a sidewall instead of metal pipe up the chimney — it produces condensate as a byproduct of combustion. That condensate drains through a small (usually 3/4”) PVC line to a floor drain, condensate pump, or exterior termination.

During a Wichita deep freeze, this line can freeze. When it does, the float switch trips and the furnace shuts down to prevent water damage.

Look for:

• A short PVC stub exiting the furnace cabinet, dripping into a floor drain or condensate pump
• A clear plastic trap somewhere in the line
• Any portion of the line running through a garage, crawlspace, or exterior wall

If any section feels ice-cold or has visible frost, thaw it with a hair dryer on low (not high — PVC warps) or warm towels. Once thawed, drain any standing water from the trap and reset the furnace by cycling the power switch. Insulate exposed sections with foam pipe insulation before the next deep cold front.

If the line froze once during this cold snap, it will freeze again. Wrap it.

5. Listen to the ignition sequence

When the thermostat calls for heat, a healthy furnace runs through this sequence — listen for each step:

1. Inducer motor spins up (small fan sound, 30–60 seconds)
2. Pressure switch closes audibly (faint click)
3. Hot surface ignitor glows orange (silent — but you may see a faint glow through the inspection port)
4. Gas valve opens (audible click + faint hiss)
5. Burners light (whoosh sound)
6. Blower motor starts 30–90 seconds later once the heat exchanger is hot

Common failure points by sound:

• Nothing happens at all: control board, transformer, or thermostat wiring
• Inducer runs but no ignition: pressure switch stuck open, blocked vent, frozen condensate
• Ignitor glows but no gas: gas valve, flame sensor, or empty propane tank (rare in Wichita; common in rural Sedgwick County)
• Burners light then shut off in 30–90 seconds: flame sensor coated with carbon — this is the single most common winter call we run
• Click-click-click then nothing: failed hot surface ignitor

6. The flame sensor (if you’re handy)

If your furnace lights, runs for 30–90 seconds, then shuts off and tries again, the flame sensor is dirty about 80% of the time. This is a thin metal rod (about 4 inches long) that sits in the burner flame and confirms combustion. Carbon and silica deposits build up on it over years of operation and eventually it stops conducting.

If you’re comfortable working inside the furnace cabinet:

1. Turn off the gas at the valve and the power at the wall switch
2. Remove the upper access panel
3. Locate the flame sensor — single wire, mounted with a single screw at the burner assembly, sitting in the path of the burner flame
4. Remove it (one screw, one wire connector)
5. Clean the metal rod with fine steel wool or 400-grit emery cloth until the metal is bright
6. Reinstall, restore power, restore gas, and run a test cycle

If you’re not comfortable doing this — that’s fine, it’s a $185–$245 service call and we do it constantly during heating season.

When to stop troubleshooting and call a Wichita HVAC tech

Pick up the phone immediately if:

• You smell gas, even faintly (leave the house first, call Kansas Gas Service at 888-482-4950 before calling us)
• The breaker has tripped twice
• You see soot, scorching, or melted plastic anywhere on the furnace cabinet
• The furnace makes a banging or popping sound when it tries to ignite (delayed ignition — dangerous)
• You see flame outside the burner box or yellow/orange flame instead of blue
• Any water is visible inside the furnace cabinet (other than the condensate trap on high-efficiency units)
• The furnace is older than 20 years and has multiple symptoms

For anything in the gas, flame, or scorching category, leave the system off until we get there. The cost of a few cold hours is far below the cost of a heat exchanger crack or a CO incident.

How Wichita HVAC Pro handles a no-heat call

We dispatch licensed Kansas HVAC techs from inside Wichita 24/7 during heating season. After-hours emergency dispatch runs $135–$185 plus parts and labor, with the dispatch fee credited toward any repair completed that night. Trucks carry common parts in stock — flame sensors, ignitors, pressure switches, inducer motors, control boards for the major brands (Carrier, Trane, Lennox, Goodman, Rheem, Bryant, American Standard) — so most repairs complete on the first visit.

We typically reach Riverside, College Hill, Eastborough, Crown Heights, and Delano within 45 minutes during a cold snap. Derby, Andover, Bel Aire, Park City, Maize, and Goddard are 60–90 minutes depending on weather. Call (316) 999-9593 and we’ll give you a real ETA, not a 4-hour window.

We diagnose, explain what we found in plain language, present a flat-rate quote before any work begins, and don’t start until you say yes. No surprise bills.

What it usually costs

Rough ranges based on what we see most weeks during Wichita heating season:

• After-hours emergency dispatch (evenings, weekends, holidays): $135–$185
• Flame sensor cleaning: $185–$245
• Flame sensor replacement: $225–$325
• Hot surface ignitor replacement: $285–$425
• Pressure switch replacement: $245–$385
• Inducer motor replacement: $485–$825
• Gas valve replacement: $385–$625
• Control board replacement: $425–$725
• Blower motor replacement: $525–$950
• Heat exchanger replacement: $1,400–$2,800 (often the moment to consider full furnace replacement)
• Full furnace replacement (96% AFUE, standard 80,000–100,000 BTU): $4,200–$6,800 installed

Diagnostic fees credit toward any repair done that day.

Common failures by furnace age

What we see fail at each life stage on Wichita furnaces:

• 0–7 years: Almost nothing. Filter changes and the occasional thermostat issue. If a furnace fails this young, it’s usually warranty work — call the installer, not us.
• 8–12 years: Flame sensors, hot surface ignitors, and pressure switches start showing up. These are wear items and replacement is routine. Don’t read failure here as the furnace dying — it’s just maintenance.
• 12–15 years: Inducer motors and gas valves enter the picture. Capacitors on the blower motor start to weaken. Annual maintenance pays off here.
• 15+ years: Blower motors, control boards, and heat exchanger cracks become the conversation. Once you’re spending $700+ on repairs at this age, run the replacement math seriously. A new 96% AFUE unit cuts gas usage 15–25% on Kansas Gas Service bills versus a 1990s 80% unit, plus you get the IRA 25C $600 federal tax credit on qualifying high-efficiency furnaces.
• 20+ years: You’re playing the lottery. Heat exchanger cracks at this age can vent CO into the home. We’re not big on scare tactics, but we’ll tell you straight: replacement is overdue.

Pre-winter prevention

Most January no-heat calls would have been avoided by a $129 tune-up in October. The tune-up walk-through:

1. Replace the air filter and set a calendar reminder for monthly checks
2. Clean the flame sensor (proactively — before it triggers a no-heat call)
3. Test the ignitor resistance and replace if outside spec
4. Inspect the heat exchanger for cracks (camera and visual)
5. Verify gas pressure is within manufacturer spec
6. Test the inducer motor and pressure switch
7. Clear the condensate line and trap (high-efficiency units)
8. Verify the CO detector in the basement or near the furnace is working — replace the batteries if it has them, replace the unit entirely if it’s older than 7 years

A pre-season tune-up runs $129–$179 and catches the failures that turn into 6 a.m. emergency calls in January. It’s the cheapest visit on our schedule and it’s almost always cheaper than the breakdown it prevents.