Whether it’s a leaky furnace or if you throw the switch to start 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 cause, knowing how your heating system works and a little bit about some common furnace problems is crucial in deciding whether you can troubleshoot on your own or if you need professional support. By monitoring 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 not sure about the problem or lack the necessary skills and tools, it's best to call a professional HVAC company like Wallpe Heating & Cooling. We can accurately diagnose 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 common heating issues:

1. My Furnace Is Leaking Water

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

It is important to deal with water leaks immediately to prevent additional damage to your furnace. Reaching out to a professional HVAC technician like the crew at Wallpe Heating & Cooling is recommended to diagnose and resolve the issue successfully.

2. My Furnace Makes 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 blocked air filter, or a malfunctioning heating element. It could also be 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 technician to diagnose and fix the problem. They can give an accurate assessment and suggest the proper solution.

3. My Furnace Can't Keep Up

A frequent 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 lower efficiency. Another reason your furnace is falling short is because it’s not powerful enough for your home, so it can’t make enough heat to adequately warm the space. A broken thermostat or ductwork problems can also cause insufficient heating.

To handle this, first check your home’s insulation level and make sure it’s enough to protect your home. Also, examine the thermostat to see if it’s set right and the batteries still function.

If the problem won’t go away, consider consulting with an experienced HVAC company, such as Wallpe Heating & Cooling, who can inspect 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 contacting a heating specialist. Ensure the thermostat is set correctly and the batteries are good. If the furnace still doesn't start, check the circuit breaker or fuse box to ensure 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 reach out to a seasoned 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 frequently at short intervals as opposed to running in regular cycles like it is designed to do. This can result in inefficiency, increased energy consumption 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 exchanged 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 ensure it is pointing in the right direction. If that doesn’t do the trick, check your thermostat and make sure  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 Wallpe Heating & Cooling. Quick 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 Is Making a Humming Noise

If your furnace is making a humming noise, it often is a sign of a malfunction with the electrical elements or the blower motor. Because of this, 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  contact a professional HVAC technician.

7. My Furnace Is Noisy

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

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 Won't Start

If your furnace will not turn on, make sure the thermostat is set to the desired temperature, is in heating mode and the batteries are working. Then, see if the circuit breaker or fuse controlling the furnace is working right. If these basic checks don't address the problem, you can examine the furnace's power switch or emergency shutoff switch to ensure they're in the "on" position and weren’t accidentally turned off.

If those steps don’t do the job, phone an expert for furnace repair.

9. My Furnace Won't Ignite

Like a 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 out the air filter and looking over your circuit breakers are a good place to start.

Other common causes of a furnace not igniting include a faulty igniter or nonfunctional flame sensor. Signs of these include the furnace continuously trying 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 simply repaired by HVAC professionals like the team at Wallpe Heating & Cooling.