Furnace Blower Keeps Running But No Heat – Troubleshooting Guide

As the temperatures drop, it’s essential to have a well-functioning furnace to keep your home warm and comfortable. However, if your furnace blower keeps running but no heat is coming out, it’s undoubtedly a cause for concern. This issue can lead to a lack of warmth, an increase in energy bills, and even potential safety hazards. But fear not, we’ve created a comprehensive guide to help you troubleshoot and solve this problem.

Why Does Your Furnace Blower Keep Running but No Heat is Coming Out?

Several factors can cause your furnace blower to run continuously without blowing any hot air. Here are some possible reasons why you might be experiencing this issue :

Clogged Air Filter

A clogged air filter can restrict the airflow in your furnace, leading to overheating and automatic shut off. When this happens, your blower continues to run, but no warm air will come out. This issue is an easy fix – simply replace your air filter and ensure to replace it regularly.

Faulty Thermostat

A malfunctioning thermostat can cause your furnace blower to run continuously without blowing any hot air. Check to see if your thermostat is set correctly and, if it’s not, adjust the temperature to the desired level. If that doesn’t work, consider replacing the thermostat altogether.

Faulty Ignition

If your furnace’s ignition system is faulty, it won’t be able to light the burners, which means no heat will be generated. You may need to contact a professional HVAC technician to diagnose and repair the problem.

Dirty Flame Sensor

A dirty flame sensor can also cause your furnace blower to run continuously without heating the air. The sensor’s job is to detect whether a flame is present, and if it’s dirty, it won’t be able to do its job correctly. Try cleaning the sensor with a soft-bristled brush, but if that doesn’t work, consider replacing it.

Faulty Limit Switch

The limit switch on your furnace is designed to detect when the temperature inside the furnace is too high, and it automatically shuts off the burner to prevent overheating. If the limit switch is faulty, it can cause your blower to keep running without producing any heat. Contact an HVAC technician to inspect and replace the limit switch if necessary.

How to Troubleshoot and Fix the Issue

If you’re experiencing the problem of your furnace blower running but no heat is coming out, here’s what you can do:

• Check your air filter : A dirty air filter can cause your furnace to overheat and shut off automatically. Replace your air filter and ensure that you replace it regularly.
• Check your thermostat : Ensure that your thermostat is set to the desired temperature and mode (heat). If it’s not, adjust it accordingly.
• Check your furnace’s ignition : If your furnace’s ignition system is faulty, contact an HVAC technician to diagnose and repair the problem.
• Clean your flame sensor : If your flame sensor is dirty, try cleaning it with a soft-bristled brush. If that doesn’t work, consider replacing it.
• Check your limit switch : If your limit switch is faulty, contact an HVAC technician to inspect and replace it.

To provide a better understanding of the topic, we have included a table summarizing the common causes and solutions for a furnace blower that keeps running but produces no heat.

Causes	Solutions
Dirty Air Filter	Replace or clean air filter
Malfunctioning Thermostat	Repair or replace thermostat
Blower Motor Issues	Repair or replace blower motor
Ignition Problems	Check ignition system, call professional for assistance
Airflow Restrictions	Clear debris from vents, ducts, and registers
Gas Supply Issues	Check gas valve and supply, call professional for assistance

Conclusion

In conclusion, a furnace blower that keeps running but produces no heat can be a serious problem that needs to be addressed promptly. As we have discussed in this article, there are various reasons why this issue might occur.

From a dirty air filter to a malfunctioning thermostat, the problem could stem from a number of factors. Therefore, it is important to diagnose the root cause of the problem and take the necessary steps to fix it.

In this article, we have outlined some of the common causes of a furnace blower running but producing no heat, as well as some troubleshooting tips to help you fix the issue. We hope that this article has been informative and helpful in resolving this issue.

If you have any questions or concerns, or if the problem persists despite your best efforts, it is recommended to seek the assistance of a professional HVAC technician.

Thank you for reading, and we wish you luck in resolving any furnace issues you may encounter.