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 affect 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 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 unsure about the problem or lack the necessary skills and tools, it's best to call an experienced HVAC company like J.L. Brady Company LLC. 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 dilemmas:

1. The Furnace Is Leaking

A furnace can leak water for several 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 plugged condensate drain line or a broken 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—leaking out of the furnace.

It is important to correct water leaks immediately to prevent additional damage to your furnace. Contacting a professional HVAC technician like the crew at J.L. Brady Company LLC is recommended to diagnose and resolve the issue effectively.

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

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 mechanism.

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

3. My Furnace Struggles to Keep Up

A widespread reason your furnace isn’t keeping up on a cold day is that your home lacks insulation, which can lead to heat loss and lower 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 completely warm the space. A broken thermostat or ductwork problems can also produce insufficient heating.

To address this, first check your home’s insulation level and make sure it’s enough to insulate your home. Also, check the thermostat to make sure it’s set right and the batteries still function.

If the problem lingers, consider consulting with an experienced HVAC company, such as J.L. Brady Company LLC, 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 calling a pro. 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 make sure power is reaching the unit.

If there is power but no heat, the problem may be with the ignition system or gas supply. In that case, it's a good idea to consult a knowledgeable HVAC technician for diagnosis and repair.

5. My Furnace Short Cycles

If your furnace is short cycling, this means it is turning on and off often at short intervals instead of running in regular cycles like it should. This can result in inefficiency, more energy use 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 make sure it is pointing in the right direction. If that doesn’t do the trick, look at your thermostat and verify  it’s set right and the batteries are good.

If those two things don’t work, it’s smart to call experts like the crew at J.L. Brady Company LLC. Immediate 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 symptom of problems with the electrical components or the blower motor. For this reason, if you hear your furnace making a humming noise, it is critical to take action.

If the noise persists, it is better that you  employ a professional HVAC technician.

7. My Furnace Is Noisy

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

Because of 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 preferred temperature, is in heating mode and the batteries are good. Then, verify that the circuit breaker or fuse that goes to the furnace is functioning properly. 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, call a heating specialist 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 plugged air filter or a tripped circuit breaker. So, inspecting the air filter and taking a peek at 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. Symptoms of these include the furnace continuously 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 very easily fixed by HVAC specialists like the team at J.L. Brady Company LLC.