Solved: Furnace Is Leaking Water and 8 Other Heating Issues

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

Regardless of the problem, knowing 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 watching 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 unsure about the problem or don't have the necessary skills and tools, it's best to call a reputable HVAC company like JTech Mechanical. We can accurately pinpoint the issue and perform the required repairs or maintenance, so we can get your furnace ready to go ASAP.

Here's more about what causes a furnace to leak water and eight other common heating problems:

1. My Furnace Is Leaking Water

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 clogged condensate drain line or a malfunctioning condensate pump. Another likely cause of water leakage from a furnace is a cracked heat exchanger, which can lead to water—as well as dangerous gases—escaping from the furnace.

It is imperative to deal with water leaks quickly to prevent more damage to your furnace. Consulting with a professional HVAC technician like the crew at JTech Mechanical is recommended to diagnose and resolve the issue effectively.

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

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

If your furnace does not blow hot air, it's better to contact a skilled HVAC tech to diagnose and fix the problem. They can give an accurate assessment and recommend 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 cause 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 effectively warm the space. A malfunctioning thermostat or ductwork problems can also produce insufficient heating.

To handle this, first look at your home’s insulation level and make sure it’s enough to protect your home. Also, examine the thermostat to make sure it’s set right and the batteries are working.

If the problem continues, consider calling an experienced HVAC company, such as JTech Mechanical, who can assess your system, determine the root cause and provide solutions such as furnace replacement, repairing ductwork or adjusting your thermostat settings.

4. My Furnace Isn't Running at All

If your furnace is not working, there are some steps you can take to troubleshoot before calling a professional. Make sure the thermostat is set properly and the batteries are fresh. If the furnace still doesn't turn on, check the circuit breaker or fuse box to make sure power is reaching the system.

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 reach out to a knowledgeable HVAC technician for diagnosis and repair.

5. My Furnace Turns On and Off

If your furnace is short cycling, this means it is turning on and off frequently at short intervals instead of running in regular cycles like it ought to. This can result in inefficiency, higher energy bills and potential damage to your heating system.

If you suspect your furnace is short cycling, the first step is to check your unit’s air filter. Filters should be switched out regularly to ensure air flow, so if your furnace air filter is clogged with debris you should exchange it for a clean one—and make 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 a good idea to call experts like the crew at JTech Mechanical. Prompt professional attention will help restore the proper functioning of your furnace and avoid more complications and high energy bills.

6. My Furnace Is Making a Humming Noise

Whenever your furnace is making a humming noise, it often is a sign of a malfunction with the electrical parts 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  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 handle the issue right away to prevent further damage or potential safety hazards.  One common cause of this is a broken blower motor or fan, which can create a grinding or screeching sound. Another possible cause is a loose or worn-out belt that may produce a squealing or rattling noise.

Because of the complexity of furnace systems and potential risks involved, it's safer 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, check if the circuit breaker or fuse that goes to the furnace is working right. If these basic checks don't resolve 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 do the job, 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 caused by a clogged air filter or a tripped circuit breaker. So, inspecting 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 faulty flame sensor. Indications 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 very easily repaired by HVAC specialists like the team at JTech Mechanical.