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

Regardless of the problem, learning how your heating system works and a little bit about some typical furnace problems is vital in deciding whether you can troubleshoot on your own or if you need professional support. By observing 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 not sure about the problem or lack the necessary skills and tools, it's best to call a professional HVAC company like Strine's. We can accurately pinpoint 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 prevalent heating dilemmas:

1. My Furnace Is Leaking Water

A furnace can leak water for several reasons. One possibility is a condensate leak, where the water created during the combustion process is not effectively draining away. This could be due to a plugged condensate drain line or a failing 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—coming out of the furnace.

It is imperative to correct water leaks immediately to prevent additional damage to your furnace. Consulting with a professional HVAC technician like the crew at Strine's is recommended to diagnose and resolve the issue successfully.

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

Some likely 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 also may 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 professional HVAC specialist to diagnose and fix the problem. They can offer an accurate assessment and suggest 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 is lacking insulation, which can cause heat loss and decreased efficiency. Another reason your furnace is falling short is because it’s too small for your home, so it can’t produce enough heat to adequately warm the space. A broken thermostat or ductwork problems can also result in inconsistent heating.

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

If the problem continues, consider contacting an experienced HVAC company, such as Strine's, 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 a few steps you can take to troubleshoot before phoning a heating specialist. Ensure the thermostat is set right and the batteries are good. If the furnace still doesn't turn on, check the circuit breaker or fuse box to ensure power is reaching the unit.

If there is power but your furnace won't ignite, the problem may lie with the ignition system or gas supply. In that case, it's better to contact a seasoned HVAC technician for diagnosis and repair.

5. My Furnace Short Cycles

If your furnace is short cycling, it means it is turning on and off often at short intervals rather than running in regular cycles like it ought to. This can lead to inefficiency, increased energy consumption and potential damage to your unit.

If you believe your furnace is short cycling, the first step is to look at your unit’s air filter. Filters should be switched out 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 be sure it is pointing in the right direction. If that doesn’t do the trick, go to your thermostat and verify  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 Strine's. 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

If your furnace is making a humming noise, it often is a symptom of an issue with the electrical elements or the blower motor. Therefore, if you hear your furnace making a humming noise, it is crucial to take action.

If the noise continues, it is best to  employ a professional HVAC technician.

7. My Furnace Makes Loud Noises

If your furnace is producing a consistent loud noise, it's important to address the issue promptly to prevent further damage or potential safety concerns.  One common cause of this is a malfunctioning 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.

Given 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 won't turn on, make sure the thermostat is set to the right temperature, is in heating mode and the batteries are working. Then, verify that the circuit breaker or fuse controlling the furnace is functioning properly. If these basic checks don't take care of the problem, you can inspect 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, contact a professional for furnace repair.

9. My Furnace Won't Ignite

Much like 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, checking out the air filter and taking a peek at your circuit breakers are a good place to start.

Other likely causes of a furnace not igniting include a faulty igniter or nonfunctional flame sensor. Symptoms of these include the furnace continually making an attempt 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 specialists like the team at Strine's.