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

Regardless of the cause, learning how your heating system works and a little bit about some typical furnace problems is crucial in deciding whether you can troubleshoot on your own or if you need professional assistance. 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 uncertain about the problem or lack the necessary skills and tools, it's best to call a reputable HVAC company like Vogts Heating & Air. We can accurately pinpoint the issue and complete 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 common heating issues:

1. My Furnace Is Leaking Water

A furnace can leak water for many reasons. One possibility is a condensate leak, where the water produced during the combustion process is not properly draining away. This might be due to a clogged condensate drain line or a malfunctioning condensate pump. Another potential 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 imperative to deal with water leaks promptly to prevent additional damage to your furnace. Contacting a professional HVAC technician like the crew at Vogts Heating & Air is recommended to diagnose and resolve the issue successfully.

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

Some potential 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 plugged air filter, or a malfunctioning heating element. It could also be your furnace is overheating and shutting off as a safety precaution.

If your furnace does not blow hot air, it's best 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 widespread reason your furnace isn’t keeping up on a cold day is that your home doesn’t have enough insulation, which can result in 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 generate enough heat to effectively warm the space. A defective thermostat or ductwork problems can also result in inconsistent heating.

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

If the problem won’t go away, consider consulting with an experienced HVAC company, such as Vogts 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 a couple of steps you can take to troubleshoot before phoning a heating specialist. 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 ensure 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 best to reach out to a knowledgeable HVAC technician for diagnosis and repair.

5. My Furnace Short Cycles

If your furnace is short cycling, it means it is turning on and off frequently at short intervals as opposed to running in regular cycles like it ought to. This can cause inefficiency, more energy use and potential damage to your unit.

If you think your furnace is short cycling, the first step is to check your unit’s air filter. Filters should be exchanged when they are dirty 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. Next, go to your thermostat and make sure  it’s set right and the batteries are good.

If those two things don’t work, it’s best to call experts like the team at Vogts 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 Hums All the Time

When your furnace is making a humming noise, it often is a sign of an issue with the electrical parts or the blower motor. For this reason, if you notice your furnace making a humming noise, it is critical to take action.

If the noise continues, it is a good idea to  employ 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 cause of this is a broken blower motor or fan, which can generate 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 in touch with a heating and cooling specialist.

8. My Furnace Can't Turn On

If your furnace will not turn on, make sure the thermostat is set to the preferred temperature, is in heating mode and the batteries are functioning. Then, see if the circuit breaker or fuse controlling the furnace is sending power to the unit. If these basic checks don't fix the problem, you can inspect 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 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 caused by a dirty air filter or a tripped circuit breaker. So, inspecting 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 faulty flame sensor. Indications of these include the furnace repeatedly 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 simply fixed by HVAC specialists like the team at Vogts Heating & Air.