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

Regardless of the issue, knowing how your heating system works and a little bit about some frequent furnace problems is crucial in deciding whether you can troubleshoot on your own or if you need professional support. By observing 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 uncertain about the problem or don't have the necessary skills and tools, it's best to call a reputable HVAC company like Halverson Brothers Inc. We can accurately pinpoint the issue and execute the required repairs or maintenance, so we can get your furnace ready to go ASAP.

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

1. Your Furnace Leaks Water

A furnace can leak water for many reasons. One possibility is a condensate leak, where the water created during the combustion process is not properly 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 result in water—as well as dangerous gases—leaking out of the furnace.

It is imperative to deal with water leaks quickly to prevent more damage to your furnace. Reaching out to a professional HVAC technician like the crew at Halverson Brothers Inc is recommended to diagnose and resolve the issue properly.

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

Some likely causes for a furnace blowing cold air or not blowing hot air include a malfunctioning thermostat, a problem with the pilot light or ignition system, a clogged air filter, or a malfunctioning heating element. It could also be your furnace is overheating and shutting off as a safety measure.

If your furnace does not blow hot air, it's best to contact a trained HVAC technician to diagnose and fix the problem. They can offer an accurate assessment and suggest the proper solution.

3. My Furnace Struggles to Keep 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 struggling is because it’s too small for your home, so it can’t make enough heat to adequately warm the space. A defective thermostat or ductwork problems can also result in uneven heating.

To deal with 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 continues, consider calling an experienced HVAC company, such as Halverson Brothers Inc, who can look over 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 some steps you can take to troubleshoot before calling a heating specialist. Check if the thermostat is set correctly and the batteries are fresh. If the furnace still doesn't start, check the circuit breaker or fuse box to verify power is reaching the furnace.

If there is power but your furnace won't blow hot air, the problem may rest with the ignition system or gas supply. In that case, it's better to reach out to an experienced HVAC technician 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 as opposed to running in regular cycles like it should. This can cause inefficiency, more energy use and potential damage to your unit.

If you suspect your furnace is short cycling, the first step is to pull out your unit’s air filter. Filters should be exchanged when they are dirty to ensure air flow, so if your furnace air filter is plugged with dirt 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 verify  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 Halverson Brothers Inc. 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 an indication of an issue with the electrical components or the blower motor. Therefore, if you detect your furnace making a humming noise, it is crucial to take action.

If the noise persists, it is a good idea to  contact a professional HVAC technician.

7. My Furnace Makes Loud Noises

If your furnace is producing a persistent loud noise, it's important to address 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 common cause is a loose or worn-out belt that may make 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 won't 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 controls the furnace is sending power to the unit. If these basic checks don't address the problem, you can inspect 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 get the job done, call a heating specialist for furnace repair.

9. My Furnace Won't Ignite

Like a a furnace that will not on at all, a furnace that isn’t igniting can be caused by 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 are a faulty igniter or nonfunctional flame sensor. Symptoms of these include the furnace continuously attempting 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 fixed by HVAC professionals like the team at Halverson Brothers Inc.