Whether it’s a leaky furnace or if you flip the switch to start 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, learning how your heating system works and a little bit about some typical furnace problems is essential in deciding whether you can troubleshoot on your own or if you need professional support. By watching 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 unsure about the problem or don't have the necessary skills and tools, it's best to call a professional HVAC company like I-Deal HVAC. We can accurately diagnose 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 common heating problems:

1. My Furnace Is Leaking Water

A furnace can leak water for several reasons. One possibility is a condensate leak, where the water produced during the combustion process is not completely draining away. This might be due to a clogged condensate drain line or a broken 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 important to address water leaks immediately to prevent further damage to your furnace. Consulting with a professional HVAC technician like the crew at I-Deal HVAC is recommended to diagnose and resolve the issue effectively.

2. My Furnace Makes Cold Air/Lack of Heat

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 clogged 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 best to contact a trained HVAC technician to diagnose and fix the problem. They can give an accurate assessment and advise you on the proper solution.

3. My Furnace Can't Keep Up

A common reason your furnace isn’t keeping up on a cold day is that your home lacks insulation, which can lead to heat loss and reduced efficiency. Another reason your furnace is struggling is because it’s too small for your home, so it can’t produce enough heat to adequately warm the space. A broken thermostat or ductwork problems can also cause insufficient heating.

To correct this, first look at 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 see if it’s set right and the batteries still function.

If the problem won’t go away, consider contacting an experienced HVAC company, such as I-Deal HVAC, 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 Is Not Working

If your furnace is not working, there are a few steps you can take to troubleshoot before phoning a heating specialist. Check if the thermostat is set correctly and the batteries are good. If the furnace still doesn't turn on, check the circuit breaker or fuse box to verify power is reaching the system.

If there is power but no heat, the problem may lie 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, this means it is turning on and off frequently at short intervals rather than running in regular cycles like it ought to. This can result in inefficiency, higher energy bills 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 changed regularly to ensure air flow, so if your furnace air filter is dirty you should exchange it for a clean one—and be sure it is pointing in the right direction. Second, go to 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 smart to call experts like the team at I-Deal HVAC. Quick professional attention will help restore the proper functioning of your furnace and prevent 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 symptom of a malfunction with the electrical parts or the blower motor. Therefore, if you detect your furnace making a humming noise, it is crucial to take action.

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

7. My Furnace Is Noisy

If your furnace is making a constant loud noise, it's important to address the issue quickly to prevent further damage or potential safety concerns.  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 safer to get a hold of 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 right temperature, is in heating mode and the batteries are good. Then, see if the circuit breaker or fuse that goes to the furnace is functioning properly. If these basic checks don't fix the problem, you can check 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, phone a heating specialist for furnace repair.

9. My Furnace Is Not Igniting

Much like 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, checking out the air filter and taking a peek at your circuit breakers are a good place to start.

Other common causes of a furnace not igniting are a faulty igniter or faulty flame sensor. Symptoms of these include the furnace repeatedly trying 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 easily addressed by HVAC professionals like the team at I-Deal HVAC.