Whether it’s a leaky furnace or if you flip the switch to power up your heating system in the fall and it won’t start, common furnace problems can strike your home at any moment.

Regardless of the problem, understanding how your heating system works and a little bit about some common furnace problems is essential in deciding whether you can troubleshoot on your own or if you need professional assistance. By monitoring the furnace's behavior, listening for peculiar noises and checking for signs of damage or blockage, you can narrow down the possible causes.

If you're uncertain about the problem or don't have the necessary skills and tools, it's best to call a reputable HVAC company like Age Heating & Cooling. We can accurately identify the issue and perform the required repairs or maintenance, so we can get your furnace working again ASAP.

Here's more about what causes a furnace to leak water and eight other frequent heating problems:

1. My Furnace Is Leaking Water

A furnace can leak water for several reasons. One possibility is a condensate leak, where the water produced during the combustion process is not effectively draining away. This could be due to a clogged condensate drain line or a broken condensate pump. Another likely cause of water leakage from a furnace is a cracked heat exchanger, which can lead to water—as well as dangerous gases—coming out of the furnace.

It is necessary to correct water leaks promptly to prevent further damage to your furnace. Contacting a professional HVAC technician like the crew at Age Heating & Cooling is recommended to diagnose and resolve the issue properly.

2. My Furnace Is Blowing Cold Air/Not Blowing Hot Air

Some potential causes for a furnace blowing cold air or not blowing hot air could be a malfunctioning thermostat, a problem with the pilot light or ignition system, a blocked air filter, or a malfunctioning heating element. It also may be your furnace is overheating and shutting off as a safety mechanism.

If your furnace won’t blow hot air, it's a good idea to contact a professional HVAC technician to diagnose and fix the problem. They can provide an accurate assessment and recommend the appropriate solution.

3. My Furnace Is Not Keeping Up

A widespread reason your furnace isn’t keeping up on a cold day is that your home doesn’t have enough insulation, which can result in heat loss and decreased efficiency. Another reason your furnace is falling short is because it’s too small for your home, so it can’t generate enough heat to effectively warm the space. A broken thermostat or ductwork problems can also result in inconsistent heating.

To address this, first look at your home’s insulation level and make sure it’s enough to keep warm air in and cold air out of your home. Also, examine the thermostat to see if it’s set right and the batteries still function.

If the problem lingers, consider contacting an experienced HVAC company, such as Age Heating & Cooling, who can inspect your system, determine the root cause and provide solutions such as furnace replacement, repairing ductwork or adjusting your thermostat settings.

4. My Furnace Is Not Working

If your furnace is not working, there are a couple of steps you can take to troubleshoot before contacting a heating specialist. Make sure the thermostat is set properly and the batteries are good. If the furnace still doesn't turn on, check the circuit breaker or fuse box to ensure power is reaching the furnace.

If there is power but your furnace won't ignite, the problem may lie with the ignition system or gas supply. In that case, it's best to consult an experienced HVAC technician for diagnosis and repair.

5. My Furnace Is Short Cycling

If your furnace is short cycling, it means it is turning on and off often at short intervals instead of running in regular cycles like it is designed to do. This can lead to inefficiency, higher energy bills and potential damage to your heating system.

If you suspect your furnace is short cycling, the first step is to check your unit’s air filter. Filters should be exchanged on a regular basis to ensure air flow, so if your furnace air filter is dirty you should exchange it for a clean one—and make sure it is pointing in the right direction. Next, go to your thermostat and make sure  it’s set right and the batteries are good.

If those two things don’t work, it’s smart to call experts like the staff at Age Heating & Cooling. Prompt professional attention will help restore the proper functioning of your furnace and reduce the chance of additional complications and high energy bills.

6. My Furnace Is Making a Humming Noise

When your furnace is making a humming noise, it often is an indication of a malfunction with the electrical hardware or the blower motor. For this reason, if you notice your furnace making a humming noise, it is crucial to take action.

If the noise persists, it is a good idea to  employ a professional HVAC technician.

7. My Furnace Is Making a Loud Noise

If your furnace is producing a constant loud noise, it's important to handle the issue promptly to prevent further damage or potential safety concerns.  One common cause of this is a failing blower motor or fan, which can generate a grinding or screeching sound. Another common cause is a loose or worn-out belt that may make a squealing or rattling noise.

Because of the complexity of furnace systems and potential risks involved, it's better to consult with a heating and cooling specialist.

8. My Furnace Is Not Turning On

If your furnace refuses to turn on, make sure the thermostat is set to the right temperature, is in heating mode and the batteries are functioning. Then, verify that the circuit breaker or fuse that goes to the furnace is working right. If these basic checks don't resolve the problem, you can check the furnace's power switch or emergency shutoff switch to ensure they're in the "on" position and weren’t accidentally turned off.

If those steps don’t work, phone a professional for furnace repair.

9. My Furnace Is Not Igniting

Similar to a furnace that will not on at all, a furnace that isn’t igniting can be caused by a dirty air filter or a tripped circuit breaker. So, examining the air filter and taking a peek at your circuit breakers are a good place to start.

Other common causes of a furnace not igniting are a faulty igniter or faulty flame sensor. Signs of these include the furnace repeatedly trying to ignite without success, a lack of heat production or the furnace is making a burning or gas smell. Both of these issues can be very easily fixed by HVAC specialists like the team at Age Heating & Cooling.