11 Furnace Problems That Require Professional Help
When your furnace is operating properly, you can keep the temperature inside comfortable. In most cases, you don’t even notice it is working when there are no issues.
Even though furnaces today are designed to have a long operating life and minimal issues, problems may still occur. The good news is that many furnace problems are simple to fix.
Unfortunately, this isn’t always the case.
Because of this, it is essential that you get to know some of the most common furnace problems that can occur and when it is time to call in the pros for help.
Keep reading to learn what these issues are.
1. No Heat
If your furnace isn’t producing heat, there’s no question it is a cause for concern.
Before calling the professionals for furnace repair, there are a few things you can check.
Check The Thermostat
Before doing anything else, make sure the thermostat is on and set on the “heat” setting. Be sure it is also set a minimum of five degrees over the temperature in the room.
Unfortunately, far too many people have called for service when this was the issue.
Along with checking the temperature, be sure to check the batteries, too. These should be changed once a year to ensure they don’t go out.
If possible, open the thermostat and blow away any dust or debris that has caused a problem. You should also ensure that the time and date are set properly for programmable models. Your system may be on a timer, and you don’t even realize it.
Reset The Circuit Breaker
Another way to try and fix a furnace that is not blowing heated air is by resetting your circuit breaker.
The circuit breaker or a fuse may trip or blow, which can cause the furnace to stop working.
It’s a good idea to go to your breaker panel and locate the circuit that provides power to your furnace. If it is in the off position, it needs to be reset. Make sure the circuit is set to “on,” which means the unit is receiving power.
If neither of these solutions fixes the “no heat” situation, it is time to call in the pros.
2. The Furnace Continues to Turn On and Off
When your furnace is working properly, it will heat your home and keep you comfortable. During this process, the unit will cycle off and on to maintain the temperature you have set on the thermostat.
How often the furnace cycles on and off depends on the temperature you have set on the thermostat and the outdoor temperature. In some cases, if there is a huge difference in these numbers, the furnace may cycle off and on a few times per hour.
However, a problem occurs if the unit starts to short cycle. This occurs when the unit turns off and on often but never reaches the temperature you have set. In most situations, this is a clear indication something is wrong.
When a furnace short cycles, it will only run for a few minutes before it shuts off again. Usually, the cause of short cycling is a lack of airflow to the unit. This can cause it to overheat.
Modern furnaces are designed with safety switches. This means if the unit gets too hot, it will shut off automatically.
Clogged air filters are one cause of restricted airflow. It can lead to overheating, and the safety switch is engaged.
If you notice the furnace is cycling off and on regularly, or if it only runs for a few minutes at a time without reaching the set temperature, try changing the air filter.
After changing the air filter, if the unit continues to short cycle, you will need a professional. They can inspect your unit and find the underlying problem.
3. Strange Sounds
When you are getting your furnace ready for winter, you need to make sure all the components are clean and working properly.
The main function of the furnace blower is to pull in heat from your furnace and then send it through your entire house. It is necessary to keep the blower well-lubricated, which is going to help your unit last longer.
There are a few steps you can use to oil your furnace blower motor. These include:
- Turn the power to the furnace off
- Remove the access panel
- Remove the blower motor
- Pull the motor out of its housing
- Find the oil ports (on the shaft and motor)
- Squeeze a few drops of oil into every port
- Turn the furnace back on
The blower motor in your furnace plays a huge role in the overall function of the heating system. If you begin to hear strange sounds coming from the unit, it is likely a sign that the blower motor needs to be lubricated.
However, if the sounds continue after you have lubricated the blower motor, a professional will need to be called to find the issue.
4. The Furnace Doesn’t Switch On Automatically
When your furnace is operating properly, it will turn on and produce heat after a signal is sent from your thermostat. If the furnace is not turning on automatically, or if it feels chilly inside, something may be wrong with the unit.
Similar to other problems with your furnace, the issue may be easy to fix. It may also be an indication of a bigger problem.
One example of a quick fix is if the circuit breaker for the unit is turned off. Be sure to check this first. Sometimes, resetting the breaker is all you have to do to get the furnace working again.
Another problem is with the thermostat. You need to make sure the setting is low enough to register that the home needs to be heated.
You can also check to ensure the unit is not set to “cool” or “off.” In these situations, the furnace will not come on.
Some of the other reasons your furnace may not be turning on automatically include:
- No fuel
- Problem with the pilot light or ignition
- Clogged air filter
If you can’t figure out the issue yourself, it’s best to call in professionals for help.
5. Cracked Heat Exchanger
If you notice the furnace’s heat exchanger is cracked, this is not an affordable or easy fix.
The heat exchanger’s job is to separate the air and warming flame. It ensures the furnace can operate safely and efficiently.
If you do not replace the filters properly or if you over-heat your house, it can cause the heat exchanger to crack.
When you suspect this is the problem, it’s best to call the professionals. They will have to replace the entire heat exchanger to restore proper function to the unit.
6. Pilot Light or Electric Ignition Issues
If you have a gas furnace, it may function through an electronic control or a pilot light. The electronic control eliminates the need for there to be a constant flame.
Faulty ignition systems, like those on furnaces equipped with a thermocouple, may reduce the ability your furnace has to heat your home effectively.
Clogs or drafts in the heating system can cause the pilot light to go out, too.
Some of the newer units available will ignite electrically instead of relying on a pilot light. If you believe there is an issue with one of these components, you can try to troubleshoot the problem yourself.
To do this, use these steps:
- Turn power to the furnace off and on
- Turn off the power and inspect the heating element for damage
- Use the user’s manual to troubleshoot potential issues
If none of these tips restore proper function to the unit, it is best to call a professional technician for an inspection.
7. Water Is Leaking from the Furnace
Some types of furnaces can develop a condensation leak. When this happens, water will pool around the furnace’s base.
If the furnace in your home is high-efficiency and has an AFUE (annual fuel utilization efficiency) that is over 90%, it probably has a cool exhaust feature.
Sometimes, a high-efficiency furnace will also have PVC exhaust pipes instead of metal ones. Usually, condensation pipes are in place too.
These will send the water produced as the fuel cools to a drain.
Sometimes, the condensation pipe can get clogged or develop a leak. If this happens, you will probably see water pooling around the furnace’s base.
When this issue occurs, it is a good idea to get in touch with a technician. They can get to the bottom of the problem.
8. Frayed or Malfunctioning Blower Belt
The blower belt in your furnace is part of the motor. It helps the fan run.
Sometimes, the belts can break or begin to fray. When this happens, you may begin to notice a high-pitched squealing sound being emitted from the furnace when it is turned on.
Replacing the belt should take care of this problem. It will also restore the performance and efficiency of the fan.
If you aren’t sure if this is the issue or the right way to replace the belt, call the professionals for help.
9. The Blower Never Shuts Off
Your furnace’s blower is located between the furnace and returns ductwork. Cool air will be sent by the blower and into the heat exchanger. The air is warmed before it goes into the plenum, and then it is carried throughout your home through the supply ducts.
If your furnace runs constantly and never shuts off, it probably needs repairs. Before calling for repairs, make sure you check to ensure the thermostat is not set on the “continuous fan” setting.
You can also turn the temperature down on the thermostat to see if this solves the issue.
When a gas furnace blower doesn’t turn off, it may be a problem with the limit control switch. You can find out for sure by contacting a technician who can repair or replace this part.
10. Ball Bearing Issues
The ball bearings in your furnace help ensure the motor works properly. As time passes, though, they may wear out.
If this happens, the ball bearings will have to be replaced.
If you begin to hear scraping noises coming out of the furnace, make sure you turn it off right away. At this point, you will need to get in touch with a professional to determine the exact issue.
11. Pinging or Rattling Sounds
Do you hear rattling, pinging, or popping sounds coming from the furnace? If so, they could be caused by several different problems.
In most cases, if you hear rattling, it is caused by loose panels that need tightening. Popping and pinging sounds are probably a problem with the ductwork.
Ducts will contract and expand based on if you are cooling or heating your house.
If the noises continue, though, it is good to get in touch with the professionals who can determine the underlying issue.
Now You Know the Most Common Furnace Problems That Require Professional Repairs
There are a lot of potential furnace problems that your unit can develop. Knowing what some of the most common are will let you know when to call for professional help.
If you notice one of these issues, don’t wait to call for service. The problem will only continue to get worse as more time passes.
Do you want to find more articles and guides on common household issues? Or do you have questions about pest control or home improvements you can make? If so, be sure to check out some of the other blogs on our website.