Solved: Furnace Leaking Water and 8 Other Furnace Problems

Whether it’s a leaky furnace or if you flick the switch to turn on your heating system when the weather gets cold and it won’t start, common furnace problems can affect 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 essential in deciding whether you can troubleshoot on your own or if you need professional assistance. By monitoring the furnace's behavior, listening for peculiar 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 249 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 dilemmas:

1. The Furnace Is Leaking

A furnace can leak water for several reasons. One possibility is a condensate leak, where the water produced during the combustion process is not properly draining away. This might be due to a clogged condensate drain line or a failing condensate pump. Another likely cause of water leakage from a furnace is a cracked heat exchanger, which can be responsible for water—as well as dangerous gases—leaking out of the furnace.

It is important to manage water leaks promptly to prevent additional damage to your furnace. Reaching out to a professional HVAC technician like the crew at 249 Air is recommended to diagnose and resolve the issue effectively.

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

Some likely 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 also may be your furnace is overheating and shutting off as a safety measure.

If your furnace will not blow hot air, it's better to contact a professional HVAC specialist to diagnose and fix the problem. They can provide an accurate assessment and suggest the proper solution.

3. My Furnace Struggles to Keep Up

A widespread reason your furnace isn’t keeping up on a cold day is that your home is lacking insulation, which can lead to heat loss and lower efficiency. Another reason your furnace is falling short is because it’s too small for your home, so it can’t generate enough heat to completely 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 keep warm air in and cold air out of your home. Also, look at the thermostat to make sure it’s set right and the batteries still function.

If the problem continues, consider calling an experienced HVAC company, such as 249 Air, who can inspect your system, determine the root cause and provide solutions such as furnace replacement, repairing ductwork or changing your thermostat settings.

4. My Furnace Won't Work

If your furnace is not working, there are a couple of steps you can take to troubleshoot before phoning a heating specialist. Check if the thermostat is set properly and the batteries are good. If the furnace still doesn't power on, check the circuit breaker or fuse box to verify power is reaching the furnace.

If there is power but your furnace won't ignite, the problem may be with the ignition system or gas supply. In that case, it's a good idea to reach out to a seasoned HVAC professional for diagnosis and repair.

5. My Furnace Is Short Cycling

If your furnace is short cycling, that means it is turning on and off often at short intervals rather than running in regular cycles like it ought to. This can lead to inefficiency, increased energy consumption and potential damage to your unit.

If you suspect your furnace is short cycling, the first step is to look at 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, 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 249 Air. Immediate professional attention will help restore the proper functioning of your furnace and prevent more complications and high energy bills.

6. My Furnace Won't Stop Humming

If your furnace is making a humming noise, it often is an indication of an issue with the electrical hardware or the blower motor. Because of this, if you detect your furnace making a humming noise, it is important to take action.

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

7. My Furnace Is Noisy

If your furnace is making a consistent loud noise, it's important to handle the issue quickly to prevent further damage or potential safety risks.  One common problem that causes 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 make a squealing or rattling noise.

Due to the complexity of furnace systems and potential risks involved, it's best to consult with 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, check if the circuit breaker or fuse that goes to the furnace is sending power to the unit. If these basic checks don't resolve the problem, you can inspect 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 work, contact an expert 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 dirty air filter or a tripped circuit breaker. So, examining the air filter and looking over your circuit breakers are a good place to start.

Other likely causes of a furnace not igniting are a faulty igniter or nonfunctional flame sensor. Indications of these include the furnace continually 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 easily solved by HVAC professionals like the team at 249 Air.