When your furnace isn’t working, it’s more than just inconvenient—it’s stressful, especially when the temperatures drop. If your furnace is running but not blowing hot air, not kicking on, or not blowing air through the vents, you’re probably wondering if it’s a quick fix… or time for a new system.
Don’t worry—we’ve seen it all, and we’re here to walk you through the most common issues, potential easy fixes, and when to call in the pros for furnace repair or replacement.
1. Furnace Not Blowing Hot Air? Start Here.
If your furnace is blowing but no heat is coming out, or it’s not blowing warm air through your vents, check these first:
- Check the thermostat settings
Make sure it’s set to “Heat” and the temperature is higher than your current room temp. - Replace the furnace filter
A dirty filter can restrict airflow, overheat the system, and stop it from blowing warm air. - Look for a tripped circuit breaker
Sometimes the furnace is fine—but the power isn’t. - Inspect the furnace switch
There’s usually a light switch nearby that turns the furnace on/off. It might have been flipped by accident.
These are common culprits, and in many cases, they’re simple DIY fixes.
2. Furnace Not Blowing Air at All?
If your furnace is running but not blowing air, the issue could be:
- Blower motor problems
This motor pushes warm air through your vents. If it’s faulty or the belt is worn, you might hear the furnace running, but nothing’s coming out. - Clogged air filter
Again, this simple issue can cause a lot of trouble. Swap it out and see if airflow improves. - Limit switch or safety switch issue
This can shut off the blower if the system is overheating.
If you’ve checked the filter and thermostat and still aren’t getting airflow, it’s time to call a furnace repair expert.
- Furnace Not Kicking On When Temperature Drops?
It’s frustrating when your furnace doesn’t kick on for heat, especially when the thermostat says “Heat On” but the furnace isn’t running. This could be due to:
- Faulty thermostat
The thermostat may not be sending the right signal to the furnace. - Ignition or pilot light failure
Without a working ignition, your furnace won’t heat at all. - Dirty flame sensor
If this sensor is dirty, the furnace may start but shut down right away.
If your system is old, ignition issues are fairly common—but fixable!
4. Furnace Running But Not Blowing Hot Air?
If the furnace turns on and makes noise, but your vents are still cold, the issue might be:
- Broken or cracked heat exchanger
This is a more serious repair and could mean it’s time for a replacement. - Gas supply issues
A problem with the gas line or valve can prevent the furnace from producing heat. - Malfunctioning gas burners
If burners are dirty or not firing correctly, they won’t heat the air.
In these cases, professional troubleshooting is your best bet.
5. Furnace Can’t Keep Up with the Cold?
If your furnace runs constantly but your home never feels warm, here are some possible reasons:
- The furnace is undersized for your home
- There’s poor insulation or leaky windows letting in cold air
- The ductwork is leaking heat before it reaches the vents
- Your furnace may be aging out
In extreme cold, it’s not unusual for older or smaller units to struggle. If your system is over 15 years old, a new furnace installation may be worth considering.
6. Furnace Repair or Replacement? How to Decide
If your furnace is acting up regularly, you might be wondering if repairs are worth it. Here’s a quick breakdown:
Age of Furnace | Repair or Replace? |
Under 10 years | Usually worth repairing |
10–15 years | Depends on repair cost and efficiency |
15+ years | Often better to replace |
The furnace repair cost will vary depending on the issue, but common repairs like replacing a blower motor, fuse, or flame sensor are usually affordable. For larger problems like a cracked heat exchanger, it may be more cost-effective to upgrade.
7. How Much Does Furnace Replacement Cost?
The average furnace replacement cost ranges from $3,500 to $7,500, depending on:
- Furnace type (gas, electric, oil)
- Size and capacity
- Efficiency rating (AFUE)
- Brand and warranty
- Installation complexity
Need something more budget-friendly? We’ll help you explore affordable options, financing, or even the best home warranty for HVAC replacement.
8. Who Can Repair My Furnace?
That’s where we come in. At Metropolitan HVAC, we offer fast, reliable furnace repair and replacement services in Camp Hill, PA, and surrounding areas. Whether your furnace fan isn’t blowing, your thermostat isn’t communicating, or your system just isn’t keeping up, we’ll find the fix and get you warm again—without the stress.
Final Thoughts: Don’t Wait Until It’s Freezing
If your furnace is not blowing heat, is making weird noises, or isn’t responding to your thermostat, it’s better to act sooner rather than later. Some issues are quick and easy to fix. Others, like system replacements, are best tackled before you’re in the middle of a cold snap.
Need fast furnace help? Call Metropolitan HVAC today or schedule a service. We’ll get your heat back on in no time—and help you feel comfortable, informed, and taken care of every step of the way.