What to Do When Your Furnace Stops Working in Extreme Cold
When Iowa temperatures drop into the single digits (or below), a furnace failure isn’t just inconvenient, it can become dangerous fast. No heat can mean frozen pipes, unsafe indoor temperatures, and costly damage if the problem isn’t addressed quickly.
If your furnace stops working during extreme cold, here’s what to do right now, what you should not attempt, and when it’s time to call for 24/7 emergency HVAC service.
Step 1: Check the Basics (But Don’t Gamble)
Before assuming the worst, take a minute to check:
Thermostat settings (heat mode, temperature set higher than room temp)
Furnace switch (accidentally bumped off happens more than you think)
Circuit breaker or fuse
Air filter (a completely clogged filter can shut a system down)
If the furnace still isn’t running stop here. Repeated restarts can make the problem worse.
Step 2: Protect Your Home From Damage
While you wait for help:
Open cabinet doors under sinks to allow warm air around plumbing
Let faucets drip slightly to reduce freezing risk
Close off unused rooms to conserve heat
Keep family members and pets in the warmest area of the home
These steps won’t fix the furnace, but they can prevent thousands of dollars in damage.
Step 3: Know When It’s an Emergency
A furnace issue should be treated as an emergency if:
Your home has no heat during extreme cold
You smell gas or burning odors
The furnace is making loud banging or screeching noises
The system shuts off repeatedly
Indoor temperatures are dropping quickly
Step 4: Avoid DIY Repairs (This Matters)
It’s tempting to search for a quick fix online, but furnace repairs involve:
Gas lines
Electrical components
Safety sensors
Combustion systems
Attempting DIY repairs can:
Void warranties
Create safety hazards
Turn a repair into a full replacement
Emergency HVAC problems are best handled by trained technicians with the right tools.
Step 5: Call for 24/7 Emergency Furnace Repair
When heat is out and temperatures are dangerous, waiting until morning isn’t always an option. A true emergency HVAC provider should be available nights, weekends, and holidays.
At Obsidian Heating & Cooling, emergency calls are prioritized during extreme weather to restore heat as quickly and safely as possible.
Why Extreme Cold Is Hard on Furnaces
During cold snaps, furnaces:
Run longer cycles
Experience more wear on ignition systems
Are more vulnerable to airflow restrictions
Can shut down due to safety lockouts
This is why emergency breakdowns often happen during the coldest nights of the year — exactly when you need heat the most.
When to Call Before It Gets Worse
If your furnace is:
Short cycling
Blowing lukewarm air
Making new or unusual noises
Struggling to keep up with the thermostat
Don’t wait for a complete failure. Early intervention can prevent an emergency altogether.
Final Thoughts
A furnace breakdown during extreme cold is stressful, but knowing what to do can make all the difference. Protect your home, avoid risky repairs, and call for help when conditions become unsafe.
