Whether it’s a leaky furnace or if you throw the switch to start your heating system when the weather gets cold and it won’t start, common furnace problems can strike your home at any moment.

Regardless of the problem, understanding 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 monitoring 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 uncertain about the problem or lack the necessary skills and tools, it's best to call a reputable HVAC company like Alpine Summit Heating & Cooling. We can accurately identify the issue and execute 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 common heating problems:

1. My Furnace Is Leaking Water

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 effectively draining away. This may be due to a blocked condensate drain line or a broken 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—coming out of the furnace.

It is imperative to correct water leaks promptly to prevent further damage to your furnace. Reaching out to a professional HVAC technician like the crew at Alpine Summit Heating & Cooling is recommended to diagnose and resolve the issue properly.

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 are 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 does not blow hot air, it's best to contact a trained HVAC specialist to diagnose and fix the problem. They can give an accurate assessment and advise you on the appropriate 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 lacks insulation, which can lead to 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 generate enough heat to completely 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 insulate your home. Also, look at the thermostat to make sure it’s set right and the batteries aren’t dead.

If the problem continues, consider consulting with an experienced HVAC company, such as Alpine Summit Heating & Cooling, who can assess your system, determine the root cause and provide solutions such as furnace replacement, repairing ductwork or modifying your thermostat settings.

4. My Furnace Is Not Working

If your furnace is not working, there are some steps you can take to troubleshoot before calling a heating specialist. Ensure the thermostat is set properly and the batteries are good. If the furnace still doesn't power 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 be with the ignition system or gas supply. In that case, it's a good idea to contact a knowledgeable HVAC professional for diagnosis and repair.

5. My Furnace Is Short Cycling

If your furnace is short cycling, that means it is turning on and off frequently at short intervals instead of running in regular cycles like it ought to. This can cause inefficiency, higher energy bills and potential damage to your heating system.

If you believe your furnace is short cycling, the first step is to look at 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 make sure it is pointing in the right direction. Second, look at 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 best to call experts like the staff at Alpine Summit Heating & Cooling. Prompt professional attention will help restore the proper functioning of your furnace and reduce the chance of more 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 a malfunction with the electrical hardware or the blower motor. For this reason, if you notice your furnace making a humming noise, it is important to take action.

If the noise doesn't go away, it is better that you  contact a professional HVAC technician.

7. My Furnace Is Making a Loud Noise

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 concerns.  One common reason is a broken blower motor or fan, which can create a grinding or screeching sound. Another potential cause is a loose or worn-out belt that may produce 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 Is Not Turning 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 working. Then, verify that 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 inspect the furnace's power switch or emergency shutoff switch to ensure they're in the "on" position and weren’t accidentally turned off.

If those steps don’t do the job, call a professional for furnace repair.

9. My Furnace Is Not Igniting

Like a a furnace not turning on at all, a furnace that isn’t igniting can be the result of a dirty 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. Symptoms of these include the furnace continually 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 simply fixed by HVAC specialists like the team at Alpine Summit Heating & Cooling.