Whether it’s a leaky furnace or if you flip the switch to start your heating system when it gets chilly and it won’t start, common furnace problems can impact your home at any moment.

Regardless of the problem, 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 support. By watching 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 not sure about the problem or aren't equipped with the necessary skills and tools, it's best to call an experienced HVAC company like Olde Towne Heating & Air. We can accurately pinpoint the issue and execute 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 prevalent heating problems:

1. My Furnace Is Leaking Water

A furnace can leak water for a number of reasons. One possibility is a condensate leak, where the water produced during the combustion process is not effectively draining away. This might be due to a plugged condensate drain line or a failing condensate pump. Another possible 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 important to manage water leaks quickly to prevent further damage to your furnace. Contacting a professional HVAC technician like the crew at Olde Towne Heating & Air is recommended to diagnose and resolve the issue effectively.

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

Some possible causes for a furnace blowing cold air or not blowing hot air are 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 mechanism.

If your furnace does not blow hot air, it's a good idea to contact a trained HVAC tech to diagnose and fix the problem. They can offer an accurate assessment and advise you on the correct solution.

3. My Furnace Is Not Keeping Up

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

To address this, first check your home’s insulation level and make sure it’s enough to protect your home. Also, check the thermostat to see if it’s set right and the batteries aren’t dead.

If the problem continues, consider consulting with an experienced HVAC company, such as Olde Towne Heating & Air, who can look over 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 some steps you can take to troubleshoot before contacting a professional. Ensure the thermostat is set right 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 system.

If there is power but your furnace won't blow hot air, the problem may lie with the ignition system or gas supply. In that case, it's a good idea to consult an experienced HVAC professional for diagnosis and repair.

5. My Furnace Is Short Cycling

If your furnace is short cycling, that means it is turning on and off frequently at short intervals instead of running in regular cycles like it ought to. This can cause inefficiency, higher energy bills and potential damage to your unit.

If you believe your furnace is short cycling, the first step is to pull out your unit’s air filter. Filters should be changed regularly to ensure air flow, so if your furnace air filter is clogged with debris you should exchange it for a clean one—and be sure it is pointing in the right direction. Second, look at 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 smart to call experts like the staff at Olde Towne Heating & Air. Quick professional attention will help restore the proper functioning of your furnace and avoid 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 a sign of an issue with the electrical parts or the blower motor. Because of this, if you detect your furnace making a humming noise, it is important to take action.

If the noise persists, it is a good idea to  get in touch with 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 deal with the issue right away to prevent further damage or potential safety hazards.  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 emit a squealing or rattling noise.

Due to the complexity of furnace systems and potential risks involved, it's better to get in touch with a heating and cooling specialist.

8. My Furnace Is Not Turning On

If your furnace won't turn on, make sure the thermostat is set to the desired temperature, is in heating mode and the batteries are working. Then, see if the circuit breaker or fuse controlling the furnace is sending power to the unit. If these basic checks don't take care of the problem, you can examine the furnace's power switch or emergency shutoff switch to verify they're in the "on" position and weren’t accidentally turned off.

If those steps don’t do the job, contact an expert for furnace repair.

9. My Furnace Is Not Igniting

Much like a furnace not turning on at all, a furnace that isn’t igniting can be the result of a plugged air filter or a tripped circuit breaker. So, checking the air filter and taking a peek at your circuit breakers are a good place to start.

Other likely causes of a furnace not igniting are a faulty igniter or faulty flame sensor. Indications of these include the furnace continuously 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 easily fixed by HVAC professionals like the team at Olde Towne Heating & Air.