Whether it’s a leaky furnace or if you flick the switch to power up 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 issue, understanding how your heating system works and a little bit about some common furnace problems is crucial in deciding whether you can troubleshoot on your own or if you need professional assistance. 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 uncertain about the problem or don't have the necessary skills and tools, it's best to call a professional HVAC company like Aggressive Mechanical. 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. 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 properly draining away. This could be due to a blocked condensate drain line or a broken condensate pump. Another likely 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 imperative to manage water leaks immediately to prevent additional damage to your furnace. Consulting with a professional HVAC technician like the crew at Aggressive Mechanical is recommended to diagnose and resolve the issue properly.
2. My Furnace Blows Cold Air/Lack of Heat
Some possible 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 a good idea to contact a trained HVAC tech to diagnose and fix the problem. They can offer an accurate assessment and advise you on the proper 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 is lacking insulation, which can lead to heat loss and lower 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 completely warm the space. A broken thermostat or ductwork problems can also result in 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 ensure it’s set right and the batteries still function.
If the problem won’t go away, consider consulting with an experienced HVAC company, such as Aggressive Mechanical, 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 Won't Work
If your furnace is not working, there are some steps you can take to troubleshoot before phoning a heating specialist. Ensure the thermostat is set correctly and the batteries are fresh. 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 your furnace won't ignite, the problem may be with the ignition system or gas supply. In that case, it's better to contact an experienced HVAC technician for diagnosis and repair.
5. My Furnace Is Short Cycling
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 is designed to do. This can cause inefficiency, more energy use and potential damage to your unit.
If you suspect your furnace is short cycling, the first step is to check your unit’s air filter. Filters should be changed when they are dirty 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. Next, 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 smart to call experts like the crew at Aggressive Mechanical. Quick professional attention will help restore the proper functioning of your furnace and avoid more complications and high energy bills.
6. My Furnace Hums All the Time
When your furnace is making a humming noise, it often is an indication of a malfunction with the electrical elements or the blower motor. Because of this, if you notice your furnace making a humming noise, it is critical to take action.
If the noise doesn't go away, it is a good idea to get in touch with a professional HVAC technician.
7. My Furnace Is Making a Loud Noise
If your furnace is making a persistent 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 common cause is a loose or worn-out belt that may emit a squealing or rattling noise.
Given the complexity of furnace systems and potential risks involved, it's better to contact a heating and cooling specialist.
8. My Furnace Can't Turn On
If your furnace refuses to turn on, make sure the thermostat is set to the preferred temperature, is in heating mode and the batteries are good. Then, verify that the circuit breaker or fuse that controls the furnace is working right. If these basic checks don't address the problem, you can examine 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 get the job done, call a heating specialist for furnace repair.
9. My Furnace Is Not Igniting
Similar to a furnace that won't turn on at all, a furnace that isn’t igniting can be the result of a dirty 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. Signs of these include the furnace continuously 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 simply repaired by HVAC professionals like the team at Aggressive Mechanical.