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

Regardless of the issue, knowing how your heating system works and a little bit about some common furnace problems is vital in deciding whether you can troubleshoot on your own or if you need professional services. By watching 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 unsure about the problem or don't have the necessary skills and tools, it's best to call a professional HVAC company like Pliescott HVAC Services LLC. We can accurately identify 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 frequent heating problems:

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 properly draining away. This might 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 result in water—as well as dangerous gases—leaking out of the furnace.

It is important to correct water leaks promptly to prevent more damage to your furnace. Reaching out to a professional HVAC technician like the crew at Pliescott HVAC Services LLC is recommended to diagnose and resolve the issue effectively.

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

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 plugged 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 will not blow hot air, it's a good idea to contact a skilled HVAC technician 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 common 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 reduced efficiency. Another reason your furnace is having difficulties 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 cause uneven heating.

To deal with this, first look at your home’s insulation level and make sure it’s enough to insulate your home. Also, look at the thermostat to see if it’s set right and the batteries aren’t dead.

If the problem continues, consider contacting an experienced HVAC company, such as Pliescott HVAC Services LLC, who can inspect your system, determine the root cause and provide solutions such as furnace replacement, repairing ductwork or adjusting your thermostat settings.

4. My Furnace Is Not Working

If your furnace is not working, there are a few steps you can take to troubleshoot before contacting a pro. Make sure the thermostat is set correctly and the batteries are good. If the furnace still doesn't power on, check the circuit breaker or fuse box to make sure 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 better to consult a seasoned 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 should. 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 pull out your unit’s air filter. Filters should be exchanged 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 make sure it is pointing in the right direction. Second, check 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 Pliescott HVAC Services LLC. Immediate professional attention will help restore the proper functioning of your furnace and reduce the chance of 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 problems with the electrical components or the blower motor. Therefore, if you detect your furnace making a humming noise, it is critical to take action.

If the noise persists, it is a good idea to  contact a professional HVAC technician.

7. My Furnace Is Making a Loud Noise

If your furnace is emitting a constant loud noise, it's important to address the issue right away to prevent further damage or potential safety hazards.  One common problem that causes this is a malfunctioning blower motor or fan, which can create 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 safer to contact a heating and cooling specialist.

8. My Furnace Is Not Turning On

If your furnace will not 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 working right. If these basic checks don't fix 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 get the job done, contact a heating specialist for furnace repair.

9. My Furnace Is Not Igniting

Like a a furnace not turning 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 assessing your circuit breakers are a good place to start.

Other likely causes of a furnace not igniting are a faulty igniter or malfunctioning flame sensor. Signs of these include the furnace repeatedly 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 repaired by HVAC specialists like the team at Pliescott HVAC Services LLC.