Solved: Furnace Leaks Water and 8 Other Heating Issues

Whether it’s a leaky furnace or if you flick the switch to power up your heating system in the fall and it won’t start, common furnace problems can affect 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 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 not sure about the problem or don't have the necessary skills and tools, it's best to call a reputable HVAC company like Better Air. We can accurately diagnose the issue and perform 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 prevalent heating issues:

1. The Furnace Is Leaking

A furnace can leak water for many 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 clogged condensate drain line or a malfunctioning 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 imperative to correct water leaks promptly to prevent additional damage to your furnace. Contacting a professional HVAC technician like the crew at Better Air is recommended to diagnose and resolve the issue effectively.

2. My Furnace Makes Cold Air/Lack of Heat

Some potential causes for a furnace blowing cold air or not blowing hot air could be a malfunctioning thermostat, a problem with the pilot light or ignition system, a clogged air filter, or a malfunctioning heating element. It could also be your furnace is overheating and shutting off as a safety mechanism.

If your furnace won’t blow hot air, it's a good idea to contact a skilled HVAC technician to diagnose and fix the problem. They can give an accurate assessment and advise you on the correct solution.

3. My Furnace Struggles to Keep Up

A frequent reason your furnace isn’t keeping up on a cold day is that your home is lacking insulation, which can result in heat loss and lower efficiency. Another reason your furnace is having difficulties is because it’s too small for your home, so it can’t generate enough heat to effectively warm the space. A malfunctioning thermostat or ductwork problems can also cause uneven heating.

To correct this, first assess your home’s insulation level and make sure it’s enough to insulate your home. Also, check the thermostat to ensure it’s set right and the batteries still function.

If the problem lingers, consider calling an experienced HVAC company, such as Better Air, 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 Isn't Running at All

If your furnace is not working, there are some steps you can take to troubleshoot before calling a pro. Check if the thermostat is set right and the batteries are not dead. If the furnace still doesn't power 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 rest with the ignition system or gas supply. In that case, it's a good idea to reach out to an experienced HVAC professional 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 rather than running in regular cycles like it is designed to do. This can cause inefficiency, more energy use and potential damage to your furnace.

If you think your furnace is short cycling, the first step is to look at your unit’s air filter. Filters should be exchanged when they are dirty to ensure air flow, so if your furnace air filter is dirty 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 best to call experts like the crew at Better Air. 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

When your furnace is making a humming noise, it often is a symptom of an issue with the electrical hardware or the blower motor. For this reason, if you detect your furnace making a humming noise, it is critical to take action.

If the noise continues, it is a good idea to  get in touch with a professional HVAC technician.

7. My Furnace Makes Loud Noises

If your furnace is producing a constant loud noise, it's important to deal with the issue right away to prevent further damage or potential safety concerns.  One common cause of this is a broken blower motor or fan, which can generate 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 best to get a hold of a heating and cooling specialist.

8. My Furnace Can't Turn On

If your furnace won't turn on, make sure the thermostat is set to the preferred temperature, is in heating mode and the batteries are working. Then, verify that 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 inspect 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 get the job done, call a heating specialist for furnace repair.

9. My Furnace Won't Ignite

Similar to a furnace that won't turn on at all, a furnace that isn’t igniting can be caused by a plugged air filter or a tripped circuit breaker. So, checking out the air filter and assessing your circuit breakers are a good place to start.

Other common causes of a furnace not igniting are a faulty igniter or faulty flame sensor. Indications of these include the furnace repeatedly trying to ignite without success, a lack of heat production or the furnace is making a burning or gas smell. Both of these issues can be very easily solved by HVAC specialists like the team at Better Air.