If you have had your furnace for a few years, you likely have accustomed to the way it operates. You may notice a gentle hum while the blower is running, or you may be used to the temporary stale odor that comes out of the vents for a few minutes after it first starts. Because of this, you may not really take notice of its operation as long as your house is kept warm.

However, you may have noticed lately that the system's operation has become more noticeable. Below are a few signs indicating that your home's electric heating system needs the immediate attention of a repair professional.

1.  Heater Does Not Kick on Until You Turn the Thermostat Way Up

One sign that there may be something amiss with your home's electric furnace is that you have to physically turn the thermostat all of the way up just to get the system started. Then, once it kicks on, you can return the setting to where you want it, and the furnace keeps operating until your house has reached the desired temperature.

While this issue could be caused by a failing thermostat, there is a possibility that a wire has become loose. Because the connection is not solid, it may take a stronger signal, such as turning up the thermostat setting, to start the heater. 

If you wish, you can try replacing the old thermostat to see if doing so fixes the issue. However, if you still have to turn the thermostat up just to make the heater kick on, there may be an issue inside of the system, such as faulty wiring, that will need to be diagnosed by a professional.

2.  Noise That Sounds like Metal Grinding Together Is Present When the Blower Is Running

Another sign that your home's furnace needs to be seen by a repair technician is when you start hearing a noise that sounds like metal grinding together. This sound is most often heard while the blower is running.

Within the blower, some bearings keep the motor moving smoothly. Over time, these bearings start to wear down. As they do, their rough surfaces will rub together, creating the noise you are hearing. This sound could also mean that the blower motor also needs oil and/or lubricant. However, you will need a professional to determine the actual cause of the grinding noise.

3.  Unusual Odor That Does Not Go Away Within a Few Minutes of the Furnace Kicking On

Along with problems starting the system and unusual noises, another sign that indicates a potential issue with the furnace is an unusual odor that does not go away within the first few minutes of the furnace kicking on. With an electrical heating system, this smell resembles one of either plastic or metal burning.

If you start to detect this odor, there is most likely a problem with the unit's wiring that needs to be addressed immediately. A faulty wire could create an arc that can short out the entire heating system, or it could even start a fire inside of the unit

If your furnace is not starting up as quickly as it should or you detect grinding noises or metallic odors while it is running, there may be a serious issue with the system. If the problem continues, the heater may break down completely, requiring costly repairs or replacement. Contact a local HVAC contractor in your area who offers heater repair services to have them inspect the unit, diagnose the cause of the problems, and take action to fix the issues that they may find.