There’s never a good time to lose heat. But if your furnace stopped working during a Colorado cold snap, things can go from uncomfortable to dangerous fast. Whether you’re waking up to a chilly house or the heat cuts out late at night, knowing what to check (and when to call for help) can make all the difference.
As local HVAC specialists, we’ve seen every kind of heating emergency. Sometimes it’s a simple fix. Other times, it’s a worn-out part or a deeper issue with your central heating system. Here’s what to do if your furnace won’t start, and how to troubleshoot your way back to a warm, safe home.
1. Check Your Thermostat First
It may sound simple, but your thermostat is the brain of your furnace. Make sure it’s set to HEAT and that the temperature is set a few degrees higher than the current room temperature. If your thermostat isn’t working, try changing the batteries or resetting it.
You should also check the fan setting. If it’s on AUTO, the blower motor will only run when the furnace is actively heating. If the fan is set to ON, it’ll blow continuously, which can confuse homeowners into thinking the heat isn’t working when it’s actually a thermostat issue.
2. Confirm Power and Fuel Supply
Even gas furnaces require electricity to run. Make sure the furnace’s power switch is set to ON, and check the breaker panel to see if the furnace breaker has tripped. If it has, reset it once. If it trips again, you’ll need professional help.
Also, check that the gas valve is fully open. If you have a propane furnace, make sure your tank has fuel and that there’s no disruption in gas supply. If you ever smell gas, especially propane, leave the house immediately and contact your gas provider and an HVAC technician.
3. Check the Furnace Filter and Airflow
If your furnace stopped working overnight, a clogged air filter could be the culprit. When airflow is blocked, the furnace can overheat and shut itself off as a safety precaution. Check your filter and replace it if it’s dirty.
Next, walk around and make sure all return air registers and supply vents are open and unobstructed. Closed vents can disrupt the air circulation system, create uneven heating, and put stress on your blower motor.
4. Look at the Pilot Light or Ignition System
Older furnaces often have a pilot light that must stay lit to ignite the burners. If the flame is out, follow your unit’s instructions to safely relight it. If you have a newer electronic ignition system, the issue may be with the ignitor sensor or furnace start sequence.
When you hear the furnace clicking but not igniting, that often means the ignitor is trying to spark, but it can’t complete the sequence. The sensor may be dirty or faulty. In some cases, you can clean the flame sensor with fine sandpaper, but if you’re unsure, it’s best to leave it to an HVAC professional.
5. Review Your User Manual and Furnace Error Codes
Many high-efficiency furnaces or condensing furnaces have small LED displays that blink error codes when something goes wrong. These codes can guide you to the issue, whether it’s the heat exchanger, combustion air, or sealed combustion system.
Refer to your manufacturer’s manual to interpret the code. If the fix is beyond your comfort level, it’s time to schedule furnace repairs or emergency furnace repair service.
6. Know When It’s Time to Call in the Pros
If you’ve checked everything above and your furnace still won’t turn on, there could be a deeper issue with your blower motor, exhaust system, or internal controls. Furnace ignition problems, short cycling, or damaged vent pipes are not DIY fixes — and waiting too long can make the problem worse.
At this point, it’s best to contact trained HVAC technicians for professional furnace troubleshooting. We have the tools to quickly diagnose issues, provide safe furnace repairs, and ensure everything is running safely, especially during extreme winter temperatures.
7. Prevent the Problem: Maintenance Matters
If your furnace shuts off in cold weather, it’s often due to a preventable issue that regular furnace maintenance could have caught. A cracked furnace heat exchanger, blocked flue, dirty burners, or deteriorating blower motor can all lead to breakdowns under pressure.
We recommend scheduling seasonal HVAC maintenance each fall to catch problems early and keep your system tuned for peak AFUE performance. That way, you’re not left wondering “why isn’t my furnace working” when you need it most.
8. Emergency Furnace Repairs You Can Count On
At Falling Star Heating and Cooling, we’re available when you need us most. Our licensed HVAC specialists respond quickly, explain what’s wrong in plain terms, make honest recommendations, and make speedy repairs. Whether your furnace stopped working suddenly or you’re dealing with an ongoing issue, we’re just a call away.
We service all types of heating systems, including forced-air furnaces, natural draft furnaces, and mid-efficiency forced draft models. Ask us today about our speedy furnace repairs in Colorado Springs. We’ll get your heat running fast — and safely.
Quick Furnace Fix Checklist
Before you call for help, try these steps:
- Check your thermostat settings and batteries
- Replace your furnace filter
- Make sure power is on and breakers haven’t tripped
- Confirm your gas supply is active
- Look for error codes or blinking lights
- Check that your pilot light or ignitor is functioning
If none of these get the heat flowing again, it’s time to call Falling Star for fast, reliable emergency furnace repairs.
Stay Warm with Preventive Furnace Maintenance
Don’t wait for your furnace to stop working again. Our affordable HVAC maintenance plans include seasonal checkups, priority service, and discounts on future furnace repairs.
Book your winter tune-up today and rest easy knowing your system is ready for whatever Colorado weather brings.
Need heat fast? Call Falling Star Heating and Cooling for emergency furnace repair in winter. We’re your local team for honest HVAC service — day or night.
Frequently Asked Questions About Furnace Problems
1. Why would a furnace quit working?
A furnace can quit working for several reasons, including a clogged air filter, thermostat issues, ignition problems, or a disruption in power or gas supply. During extreme cold, worn components like the blower motor or ignitor are more likely to fail, especially if furnace maintenance has been skipped.
2. How do I reset my furnace?
Most furnaces can be reset by turning off the power switch near the unit, waiting 30 seconds, and turning it back on. If your furnace stopped working again after a reset or shows error codes, it’s best to stop resetting and call HVAC technicians to avoid further damage. The U.S. Department of Energy recommends professional service when heating systems repeatedly shut down due to safety controls.
3. Is a furnace not working an emergency?
Yes, a furnace not working can be an emergency, especially during a cold snap or if indoor temperatures drop below safe levels. Emergency furnace repairs are critical if there’s no heat in winter, risk of frozen pipes, or anyone in the home who is elderly, ill, or very young.
4. What are signs of a failing furnace?
Common signs include uneven heating, strange noises, frequent cycling, rising energy bills, or a furnace that shuts off in cold weather. If you notice repeated ignition problems, weak airflow, or your furnace stopped working overnight more than once, those are strong indicators that furnace repairs or replacement may be needed.
5. Why isn’t my furnace working even though it has power?
If the furnace has power but won’t start, the issue could be a dirty flame sensor, failed ignitor, blocked exhaust system, or lack of combustion air. Safety switches are designed to shut the system down when something isn’t right, which is why professional furnace troubleshooting is often required.
6. What should I do while waiting for emergency furnace repairs?
While waiting for HVAC specialists, keep doors closed to retain heat, open blinds during the day for solar warmth, and use safe supplemental heat if available. Avoid using ovens or unsafe heaters for warmth, and follow heating safety guidance from the U.S. Fire Administration to reduce fire risk during no‑heat emergencies.
