Solved: Furnace Leaking Water and 8 Other Furnace Problems

Whether it’s a leaky furnace or if you flip the switch to turn on 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 vital in deciding whether you can troubleshoot on your own or if you need professional services. By noting 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 lack the necessary skills and tools, it's best to call a professional HVAC company like Kapaun & Brown. We can accurately diagnose the issue and perform 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 frequent heating problems:

1. The Furnace Is Leaking

A furnace can leak water for a number of reasons. One possibility is a condensate leak, where the water released during the combustion process is not effectively draining away. This might be due to a plugged condensate drain line or a malfunctioning condensate pump. Another potential cause of water leakage from a furnace is a cracked heat exchanger, which can lead to water—as well as dangerous gases—coming out of the furnace.

It is imperative to deal with water leaks promptly to prevent further damage to your furnace. Reaching out to a professional HVAC technician like the crew at Kapaun & Brown is recommended to diagnose and resolve the issue properly.

2. My Furnace Makes Cold Air/Lack of Heat

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

If your furnace won’t blow hot air, it's better to contact a professional HVAC tech to diagnose and fix the problem. They can provide an accurate assessment and recommend the correct solution.

3. My Furnace Can't Keep Up

A frequent 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 lower efficiency. Another reason your furnace is falling short is because it’s not powerful enough for your home, so it can’t make enough heat to adequately warm the space. A malfunctioning thermostat or ductwork problems can also produce uneven heating.

To deal with this, first check your home’s insulation level and make sure it’s enough to protect your home. Also, check the thermostat to see if it’s set right and the batteries aren’t dead.

If the problem lingers, consider consulting with an experienced HVAC company, such as Kapaun & Brown, 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 Isn't Running at All

If your furnace is not working, there are a few steps you can take to troubleshoot before contacting a professional. Make sure the thermostat is set correctly and the batteries are fresh. 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 your furnace won't ignite, the problem may rest with the ignition system or gas supply. In that case, it's a good idea to reach out to an experienced HVAC professional for diagnosis and repair.

5. My Furnace Is Short Cycling

If your furnace is short cycling, this means it is turning on and off multiple times at short intervals as opposed to running in regular cycles like it should. This can lead to inefficiency, higher energy bills and potential damage to your heating system.

If you believe your furnace is short cycling, the first step is to check your unit’s air filter. Filters should be switched out on a regular basis 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. Next, look at your thermostat and make sure  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 Kapaun & Brown. Prompt professional attention will help restore the proper functioning of your furnace and reduce the chance of additional complications and high energy bills.

6. My Furnace Hums All the Time

Whenever your furnace is making a humming noise, it often is a sign of problems with the electrical components or the blower motor. For this reason, if you hear your furnace making a humming noise, it is critical to take action.

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

7. My Furnace Is Making a Loud Noise

If your furnace is producing a persistent loud noise, it's important to handle 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 generate a grinding or screeching sound. Another possible cause is a loose or worn-out belt that may make a squealing or rattling noise.

Due to 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 Won't Start

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, see if the circuit breaker or fuse controlling the furnace is working right. 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 do the job, phone a heating specialist for furnace repair.

9. My Furnace Won't Ignite

Much like a furnace not turning on at all, a furnace that isn’t igniting can be the result of a plugged air filter or a tripped circuit breaker. So, checking the air filter and looking over your circuit breakers are a good place to start.

Other common causes of a furnace not igniting are a faulty igniter or nonfunctional flame sensor. Signs of these include the furnace repeatedly making an attempt 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 solved by HVAC specialists like the team at Kapaun & Brown.