Solved: Furnace Leaking Water and 8 Other Furnace Problems

Whether it’s a leaky furnace or if you flick 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, 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 support. By observing 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 uncertain about the problem or don't have the necessary skills and tools, it's best to call a professional HVAC company like SKC AC LLC. 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 frequent heating dilemmas:

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 completely draining away. This might 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 result in water—as well as dangerous gases—escaping from the furnace.

It is necessary to deal with water leaks quickly to prevent more damage to your furnace. Reaching out to a professional HVAC technician like the crew at SKC AC LLC is recommended to diagnose and resolve the issue successfully.

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

Some likely causes for a furnace blowing cold air or not blowing hot air could be a malfunctioning thermostat, a problem with the pilot light or ignition system, a blocked 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 better to contact a professional HVAC tech to diagnose and fix the problem. They can offer an accurate assessment and advise you on the appropriate solution.

3. My Furnace Is Not Keeping Up

A frequent 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 falling short is because it’s not big enough for your home, so it can’t make enough heat to completely warm the space. A malfunctioning thermostat or ductwork problems can also result in insufficient heating.

To deal with this, first look at your home’s insulation level and make sure it’s enough to protect your home. Also, check the thermostat to make sure it’s set right and the batteries are working.

If the problem continues, consider consulting with an experienced HVAC company, such as SKC AC LLC, 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 Is Not Working

If your furnace is not working, there are some steps you can take to troubleshoot before contacting a pro. Check if 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 system.

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 a good idea to contact an experienced HVAC technician for diagnosis and repair.

5. My Furnace Is Short Cycling

If your furnace is short cycling, that means it is turning on and off multiple times at short intervals instead of running in regular cycles like it is designed to do. This can cause inefficiency, increased energy consumption 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 switched out regularly to ensure air flow, so if your furnace air filter is dirty 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 make sure  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 SKC AC LLC. Quick professional attention will help restore the proper functioning of your furnace and reduce the chance of further 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 a malfunction with the electrical components or the blower motor. Because of this, if you notice your furnace making a humming noise, it is important to take action.

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

7. My Furnace Makes Loud Noises

If your furnace is making a constant loud noise, it's important to address the issue quickly to prevent further damage or potential safety risks.  One common cause of this is a malfunctioning blower motor or fan, which can make a grinding or screeching sound. Another potential cause is a loose or worn-out belt that may produce a squealing or rattling noise.

Given the complexity of furnace systems and potential risks involved, it's best 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 desired temperature, is in heating mode and the batteries are functioning. Then, check 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 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 work, call a professional 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 clogged air filter or a tripped circuit breaker. So, examining the air filter and looking over 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 repeatedly 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 easily fixed by HVAC pros like the team at SKC AC LLC.