Whether it’s a leaky furnace or if you flick the switch to turn on your heating system when it gets chilly and it won’t start, common furnace problems can impact your home at any moment.

Regardless of the problem, learning how your heating system works and a little bit about some common furnace problems is essential in deciding whether you can troubleshoot on your own or if you need professional services. By noting 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 aren't equipped with the necessary skills and tools, it's best to call an experienced HVAC company like All Solutions Heating & Cooling. We can accurately identify the issue and execute 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 issues:

1. Your Furnace Leaks 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 properly draining away. This could be due to a clogged condensate drain line or a failing 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—coming out of the furnace.

It is imperative to correct water leaks quickly to prevent further damage to your furnace. Contacting a professional HVAC technician like the crew at All Solutions Heating & Cooling is recommended to diagnose and resolve the issue properly.

2. My Furnace Is Blowing Cold Air/Lack of Heat

Some likely 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 could also be your furnace is overheating and shutting off as a safety measure.

If your furnace won’t blow hot air, it's a good idea to contact a skilled HVAC tech to diagnose and fix the problem. They can provide an accurate assessment and recommend the appropriate 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 lower efficiency. Another reason your furnace is struggling is because it’s not powerful enough for your home, so it can’t produce enough heat to effectively warm the space. A defective thermostat or ductwork problems can also result in uneven heating.

To correct this, first assess 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 are working.

If the problem won’t go away, consider consulting with an experienced HVAC company, such as All Solutions 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 Isn't Running at All

If your furnace is not working, there are a few steps you can take to troubleshoot before phoning a professional. 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 unit.

If there is power but your furnace won't blow hot air, the problem may be with the ignition system or gas supply. In that case, it's best to contact 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 often at short intervals rather than running in regular cycles like it is designed to do. This can result in inefficiency, more energy use and potential damage to your furnace.

If you think your furnace is short cycling, the first step is to look at your unit’s air filter. Filters should be changed 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. If that doesn’t do the trick, 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 a good idea to call experts like the staff at All Solutions Heating & Cooling. Prompt professional attention will help restore the proper functioning of your furnace and prevent further complications and high energy bills.

6. My Furnace Won't Stop Humming

Whenever your furnace is making a humming noise, it often is an indication of an issue with the electrical elements or the blower motor. For this reason, if you hear your furnace making a humming noise, it is important to take action.

If the noise persists, 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 address the issue promptly to prevent further damage or potential safety concerns.  One common problem that causes this is a malfunctioning blower motor or fan, which can make a grinding or screeching sound. Another possible cause is a loose or worn-out belt that may emit a squealing or rattling noise.

Due to the complexity of furnace systems and potential risks involved, it's better to consult with a heating and cooling specialist.

8. My Furnace Is Not Turning On

If your furnace won't 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 controls the furnace is sending power to the unit. If these basic checks don't take care of the problem, you can examine 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 work, call a professional for furnace repair.

9. My Furnace Won't Ignite

Similar to a furnace that won't turn on at all, a furnace that isn’t igniting can be caused by a dirty air filter or a tripped circuit breaker. So, checking 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 could be a faulty igniter or faulty flame sensor. Symptoms 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 easily solved by HVAC professionals like the team at All Solutions Heating & Cooling.