Whether it’s a leaky furnace or if you throw the switch to power up your heating system when the weather gets cold 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 assistance. By watching the furnace's behavior, listening for strange 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 don't have the necessary skills and tools, it's best to call a professional HVAC company like B & B Heating & Cooling. We can accurately pinpoint the issue and complete 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 issues:

1. The Furnace Is Leaking

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 properly draining away. This could be due to a blocked condensate drain line or a malfunctioning 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 address water leaks promptly to prevent more damage to your furnace. Reaching out to a professional HVAC technician like the crew at B & B Heating & Cooling is recommended to diagnose and resolve the issue properly.

2. My Furnace Blows Cold Air/Lack of Heat

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 plugged air filter, or a malfunctioning heating element. It is also possible your furnace is overheating and shutting off as a safety measure.

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

3. My Furnace Is Not Keeping Up

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

To address this, first assess your home’s insulation level and make sure it’s enough to keep warm air in and cold air out of your home. Also, look at the thermostat to make sure it’s set right and the batteries aren’t dead.

If the problem lingers, consider contacting an experienced HVAC company, such as B & B Heating & Cooling, who can inspect 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 couple of steps you can take to troubleshoot before contacting a professional. Make sure the thermostat is set right and the batteries are good. If the furnace still doesn't start, check the circuit breaker or fuse box to verify power is reaching the system.

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

5. My Furnace Is Short Cycling

If your furnace is short cycling, this means it is turning on and off multiple times at short intervals instead of running in regular cycles like it should. This can cause inefficiency, more energy use and potential damage to your furnace.

If you think your furnace is short cycling, the first step is to check your unit’s air filter. Filters should be changed regularly to ensure air flow, so if your furnace air filter is plugged with dirt you should exchange it for a clean one—and be sure it is pointing in the right direction. Next, check 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 B & B Heating & Cooling. Quick professional attention will help restore the proper functioning of your furnace and avoid more complications and high energy bills.

6. My Furnace Hums All the Time

If your furnace is making a humming noise, it often is a sign of problems 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 better that you  contact a professional HVAC technician.

7. My Furnace Is Making a Loud Noise

If your furnace is emitting a persistent loud noise, it's important to handle the issue quickly to prevent further damage or potential safety risks.  One common problem that causes this is a broken blower motor or fan, which can create a grinding or screeching sound. Another possible cause is a loose or worn-out belt that may emit a squealing or rattling noise.

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

8. My Furnace Won't Start

If your furnace refuses to turn on, make sure the thermostat is set to the desired temperature, is in heating mode and the batteries are functioning. Then, check if the circuit breaker or fuse that goes to the furnace is working right. 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 work, call a professional for furnace repair.

9. My Furnace Is Not Igniting

Like a a furnace that will not 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 assessing your circuit breakers are a good place to start.

Other potential causes of a furnace not igniting include a faulty igniter or malfunctioning flame sensor. Indications of these include the furnace continually 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 repaired by HVAC professionals like the team at B & B Heating & Cooling.