Whether it’s a leaky furnace or if you flick the switch to turn on your heating system when the weather gets cold and it won’t start, common furnace problems can affect your home at any moment.

Regardless of the cause, understanding how your heating system works and a little bit about some typical furnace problems is vital in deciding whether you can troubleshoot on your own or if you need professional services. By watching the furnace's behavior, listening for unusual noises and checking for signs of damage or blockage, you can narrow down the possible causes.

If you're not sure about the problem or lack the necessary skills and tools, it's best to call a professional HVAC company like Franklin's Heating & Air Conditioning, Inc. We can accurately diagnose the issue and perform the required repairs or maintenance, so we can get your furnace up and running ASAP.

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

1. My Furnace Is Leaking Water

A furnace can leak water for many reasons. One possibility is a condensate leak, where the water produced during the combustion process is not completely draining away. This might 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 be responsible for water—as well as dangerous gases—leaking out of the furnace.

It is imperative to correct water leaks promptly to prevent more damage to your furnace. Contacting a professional HVAC technician like the crew at Franklin's Heating & Air Conditioning, Inc is recommended to diagnose and resolve the issue effectively.

2. My Furnace Is Blowing Cold Air/Lack of Heat

Some likely 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 clogged air filter, or a malfunctioning heating element. It is also possible your furnace is overheating and shutting off as a safety precaution.

If your furnace will not blow hot air, it's better to contact a professional HVAC specialist to diagnose and fix the problem. They can offer an accurate assessment and suggest the appropriate solution.

3. My Furnace Can't Keep Up

A widespread reason your furnace isn’t keeping up on a cold day is that your home is lacking insulation, which can lead to heat loss and decreased efficiency. Another reason your furnace is having difficulties is because it’s not big enough for your home, so it can’t generate enough heat to effectively warm the space. A broken thermostat or ductwork problems can also cause uneven heating.

To handle this, first look at your home’s insulation level and make sure it’s enough to protect your home. Also, examine the thermostat to make sure it’s set right and the batteries aren’t dead.

If the problem lingers, consider calling an experienced HVAC company, such as Franklin's Heating & Air Conditioning, Inc, who can look over your system, determine the root cause and provide solutions such as furnace replacement, repairing ductwork or modifying 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 phoning a heating specialist. Make sure the thermostat is set properly and the batteries are fresh. If the furnace still doesn't power on, check the circuit breaker or fuse box to make sure power is reaching the furnace.

If there is power but no heat, the problem may be with the ignition system or gas supply. In that case, it's better to contact an experienced HVAC professional for diagnosis and repair.

5. My Furnace Turns On and Off

If your furnace is short cycling, that means it is turning on and off often at short intervals rather than running in regular cycles like it ought to. This can result in inefficiency, higher energy bills and potential damage to your heating system.

If you believe 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 ensure it is pointing in the right direction. If that doesn’t do the trick, go to your thermostat and look to see if  it’s set right and the batteries are good.

If those two things don’t work, it’s best to call experts like the team at Franklin's Heating & Air Conditioning, Inc. Immediate professional attention will help restore the proper functioning of your furnace and avoid additional complications and high energy bills.

6. My Furnace Hums All the Time

If your furnace is making a humming noise, it often is a symptom of an issue with the electrical parts or the blower motor. Therefore, if you hear your furnace making a humming noise, it is crucial to take action.

If the noise continues, it is a good idea to  get in touch with a professional HVAC technician.

7. My Furnace Makes Loud Noises

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

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

8. My Furnace Can't Turn On

If your furnace refuses to turn on, make sure the thermostat is set to the preferred temperature, is in heating mode and the batteries are good. Then, verify that the circuit breaker or fuse controlling the furnace is working right. If these basic checks don't fix the problem, you can inspect 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 do the job, phone an expert for furnace repair.

9. My Furnace Is Not Igniting

Similar to a furnace not turning on at all, a furnace that isn’t igniting can be the result of a clogged air filter or a tripped circuit breaker. So, checking out the air filter and looking over your circuit breakers are a good place to start.

Other likely causes of a furnace not igniting could be a faulty igniter or malfunctioning flame sensor. Indications of these include the furnace continuously making an attempt 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 easily addressed by HVAC specialists like the team at Franklin's Heating & Air Conditioning, Inc.