Solved: Furnace Is Leaking Water and 8 Other Furnace Problems

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

Regardless of the cause, understanding 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 assistance. 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 Tokay. 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 problems:

1. The Furnace Is Leaking

A furnace can leak water for several reasons. One possibility is a condensate leak, where the water created during the combustion process is not completely draining away. This could 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 manage water leaks quickly to prevent additional damage to your furnace. Contacting a professional HVAC technician like the crew at Tokay is recommended to diagnose and resolve the issue properly.

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

Some potential 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 is also possible your furnace is overheating and shutting off as a safety precaution.

If your furnace will not blow hot air, it's better to contact a skilled 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 doesn’t have enough insulation, which can cause heat loss and decreased efficiency. Another reason your furnace is struggling is because it’s too small for your home, so it can’t make enough heat to completely warm the space. A defective thermostat or ductwork problems can also result in uneven heating.

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

If the problem lingers, consider consulting with an experienced HVAC company, such as Tokay, 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 Won't Work

If your furnace is not working, there are some steps you can take to troubleshoot before calling a professional. Check if the thermostat is set right and the batteries are fresh. If the furnace still doesn't start, check the circuit breaker or fuse box to verify 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 consult a seasoned HVAC technician for diagnosis and repair.

5. My Furnace Short Cycles

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 ought to. This can result in inefficiency, more energy use and potential damage to your heating system.

If you believe your furnace is short cycling, the first step is to pull out your unit’s air filter. Filters should be changed on a regular basis to ensure air flow, so if your furnace air filter is clogged with debris you should exchange it for a clean one—and be sure it is pointing in the right direction. Next, check 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 team at Tokay. Quick professional attention will help restore the proper functioning of your furnace and prevent more complications and high energy bills.

6. My Furnace Is Making a Humming Noise

If your furnace is making a humming noise, it often is an indication of an issue with the electrical components or the blower motor. For this reason, if you notice your furnace making a humming noise, it is critical to take action.

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

7. My Furnace Is Making a Loud Noise

If your furnace is producing a consistent loud noise, it's important to deal with the issue quickly to prevent further damage or potential safety risks.  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 make a squealing or rattling noise.

Due to the complexity of furnace systems and potential risks involved, it's best 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 right temperature, is in heating mode and the batteries are working. Then, see if the circuit breaker or fuse controlling the furnace is sending power to the unit. 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 work, call a professional for furnace repair.

9. My Furnace Is Not Igniting

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, inspecting the air filter and assessing your circuit breakers are a good place to start.

Other common causes of a furnace not igniting could be a faulty igniter or malfunctioning flame sensor. Symptoms of these include the furnace continually 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 very easily fixed by HVAC pros like the team at Tokay.