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

Regardless of the cause, 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 support. 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 not sure about the problem or aren't equipped with the necessary skills and tools, it's best to call a reputable HVAC company like Bell Air Conditioning Inc. We can accurately pinpoint 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 frequent heating dilemmas:

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 created during the combustion process is not properly draining away. This may be due to a clogged condensate drain line or a failing condensate pump. Another possible cause of water leakage from a furnace is a cracked heat exchanger, which can be responsible for water—as well as dangerous gases—escaping from the furnace.

It is imperative to manage water leaks immediately to prevent additional damage to your furnace. Reaching out to a professional HVAC technician like the crew at Bell Air Conditioning Inc 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 plugged 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 trained HVAC specialist to diagnose and fix the problem. They can provide an accurate assessment and suggest the proper solution.

3. My Furnace Can't Keep Up

A frequent reason your furnace isn’t keeping up on a cold day is that your home doesn’t have enough insulation, which can lead to heat loss and decreased efficiency. Another reason your furnace is struggling is because it’s not big enough for your home, so it can’t make enough heat to effectively warm the space. A malfunctioning thermostat or ductwork problems can also produce insufficient heating.

To handle this, first look at your home’s insulation level and make sure it’s enough to insulate your home. Also, look at the thermostat to make sure it’s set right and the batteries are working.

If the problem lingers, consider contacting an experienced HVAC company, such as Bell Air Conditioning Inc, who can assess your system, determine the root cause and provide solutions such as furnace replacement, repairing ductwork or changing your thermostat settings.

4. My Furnace Isn't Running at All

If your furnace is not working, there are a few steps you can take to troubleshoot before phoning a pro. Make sure the thermostat is set right and the batteries are good. 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 your furnace won't blow hot air, the problem may be with the ignition system or gas supply. In that case, it's a good idea to consult a seasoned 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 multiple times at short intervals rather than running in regular cycles like it should. This can lead to inefficiency, higher energy bills and potential damage to your heating system.

If you think your furnace is short cycling, the first step is to look at your unit’s air filter. Filters should be switched out on a regular basis to ensure air flow, so if your furnace air filter is clogged with debris you should exchange it for a clean one—and ensure it is pointing in the right direction. Second, check 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 a good idea to call experts like the team at Bell Air Conditioning Inc. Prompt professional attention will help restore the proper functioning of your furnace and avoid more complications and high energy bills.

6. My Furnace Is Making a Humming Noise

If your furnace is making a humming noise, it often is a sign of a malfunction with the electrical elements or the blower motor. For this reason, if you hear your furnace making a humming noise, it is crucial to take action.

If the noise doesn't go away, it is a good idea to  contact a professional HVAC technician.

7. My Furnace Is Noisy

If your furnace is making a constant loud noise, it's important to deal with the issue quickly to prevent further damage or potential safety hazards.  One common reason is a failing blower motor or fan, which can generate 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 safer to get in touch with 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 right temperature, is in heating mode and the batteries are functioning. Then, check if the circuit breaker or fuse controlling the furnace is working right. If these basic checks don't fix the problem, you can examine the furnace's power switch or emergency shutoff switch to make sure 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 Won't Ignite

Like a a furnace not turning on at all, a furnace that isn’t igniting can be caused by a plugged air filter or a tripped circuit breaker. So, examining the air filter and assessing your circuit breakers are a good place to start.

Other potential causes of a furnace not igniting could be a faulty igniter or nonfunctional flame sensor. Indications of these include the furnace continually attempting to ignite without success, an absence of heat production or the furnace is making a burning or gas smell. Both of these issues can be simply repaired by HVAC pros like the team at Bell Air Conditioning Inc.