4 Things To Do When You Have A Furnace Not Blowing Hot Air


During the cold season, your home’s furnace plays an essential role in providing hot air inside the property. Typically, a furnace, which is commonly called a heater or boiler, refers to equipment that’s designed to heat up an entire property using a heating coil or flame. 

However, when your furnace isn’t blowing hot air, it can be a sign that there’s something wrong with your equipment, and it needs some troubleshooting to address the problem before it further deteriorates. 

Keep reading this article to know the four things to do when you have a furnace that isn’t producing hot air, especially during the cold season:

  1. Set The Thermostat’s Setting Into ‘Auto’ Mode

When you notice your furnace is blowing cold air instead of the hot one, it can be due to a thermostat fan setting that needs to be placed to ‘auto.’ Generally, the fan setting is an important part of your furnace because it helps regulate the blower which is used to circulate air around your home. That’s why if your thermostat is set to ‘on,’ it means the blower will have to operate round the clock, which will blow hot or cold air. 

Hence, to make sure your furnace is only blowing hot air, you should check the fan setting of your thermostat and see to it that it’s adjusted to auto. By doing this, you can make sure the blower will function when the furnace is heating the air. 

  1. Examine The Filter And Determine If It’s Dirty

Another thing to do when your furnace isn’t producing hot air is to check whether the filter is dirty. When you have a filthy air filter, it blocks the airflow through your heat exchanges which causes the furnace to overheat. As a result, the burners will shut off, causing the furnace to blow cold air instead of hot. 

Due to these circumstances, it’s important to inspect your air filter from time to time to ensure it’s clean and in good working condition. If it’s full of blockages, don’t hesitate to change it as soon as possible to avoid further furnace issues. 

But, if you believe this task can be best handled by a professional, call someone who can do the job for you more efficiently. There are many companies out there that offer furnace installation and replacement services in your area. 

Moreover, these service providers provide expert tips on various topics, such as this guide to help you handle some furnace problems. Thus, they become a reliable source of information online. 

  1. Check If the Condensate Line Is Blocked

If you notice water pooling around the furnace, it can be due to a blockage which may cause the furnace to shut down eventually and blow cold air. Generally, when you’re running a highly efficient furnace, then you should expect it to produce water, commonly known as condensate, which is flushed out through the drain line. 

However, if the drain line is blocked by ice, dust, dirt, or mold, the condensate remains in the furnace and causes it to automatically shut down to prevent further damage. When this happens, the furnace can no longer blow hot air throughout your home. 

For this reason, you should find time to check the condensate line regularly to avoid dealing with some problems. When you see some blockages, unclog the line so the condensate will be drained properly. And just like the boiler spare parts that you may need to backup, you should also get ready with some furnace spare parts such as those needed to fix the condensate line for troubleshooting and repairs. 

  1. Inspect The Pilot Light If It’s On

When your furnace isn’t able to blow hot air, make sure to examine the pilot light and see if it’s on. In most cases, if the standing pilot light isn’t igniting, there’s a high chance your furnace’s burner isn’t also working and blowing hot air. To remedy this situation, you should relight or reset the settings of the pilot light using the following steps:

  • Turn off the thermostat.
  • Locate the assembly for pilot light, including the switch for resetting, which is often situated not far away from the bottom of the furnace. 
  • Using the switch for resetting, place the knot to ‘off’ for three to five minutes. 
  • Then, set it again to ‘pilot’ mode by pressing it down to restart the gas flow. 
  • Light the furnace through the opening of the pilot light.
  • Set the knot again to ‘on’ mode to ignite the furnace. 
  • Turn on the thermostat and ensure the room temperature level is adjusted below five degrees to get the hot air your home requires. 

The Bottom Line

Indeed, having a furnace that’s in perfect working condition is important to maintain a good temperature level on your property. This is especially true if you need hot air to circulate around your home during the cold season. However, there are instances wherein your furnace may not function properly and blow hot air just like what you need. 

Luckily, by keeping these things in mind, you can easily troubleshoot the problem and address it in the fastest time possible. But, if your face isn’t still blowing hot air after troubleshooting, it’s best to hire an HVAC (heating, ventilation, and air conditioning) technician to help you. That way, you can make sure your furnace repair will be best handled by the best professional in your area.