How to Troubleshoot a Furnace

Author Joel Sims

Posted Apr 26, 2023

Reads 8.3K

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Are you experiencing furnace not working simple fixes? Don't panic just yet. Before calling a professional furnace technician or your trusted furnace company, try troubleshooting the problem yourself. With modern high-efficiency furnaces, many common problems can be fixed with a few easy steps and minimal time investment - total time 15 mins or less.

While furnaces may seem like complex pieces of machinery, most issues are caused by simple problems such as power supply interruptions, thermostat malfunctions, or a clogged condensate drain system. Trying to fix these issues yourself makes sense as it can save you from a substantial service call charge for major repairs. By learning how to troubleshoot your furnace, you can quickly diagnose and fix small problems without having to wait for a professional furnace technician to come out and repair it.

Understanding the Fundamentals of Furnace Repair

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Understanding the Fundamentals of Furnace Repair is crucial to keeping this important appliance running smoothly. Your furnace plays a key role in making your house livable during cold weather, providing warmth and hot water. If your furnace isn't working, dropping you'll want to find simple solutions before calling in a repair tech.

There are a fair number of common furnace problems that can be fixed without an expensive service call. For gas-fired forced-air furnaces, start by checking the thermostat settings and ensuring the pilot light is lit. For electric furnace systems, check the circuit breaker and replace any blown fuses. Hot water boilers may need their water level checked or air purged from the system.

Before you spend big bucks on a repair tech, try some basic checks that apply to many furnace types. Change or clean your air filter regularly, as this can help improve airflow and prevent overheating. Inspect exhaust vents for blockages that could cause carbon monoxide buildup. With a little understanding of how your furnace works and some basic troubleshooting skills, you can keep it running smoothly for years to come!

Bonus Common Furnace Problem: Furnace Not Working After Changing Filter

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Changing your furnace filter is an important task to ensure that your furnace runs efficiently. However, one common problem that homeowners face after changing their furnace filter is that the furnace stops working. There can be several common reasons for this, but the most likely culprit is the door switch safety.

When you change your air filter, you may have to remove the furnace door to access it. If the furnace door isn't properly installed or accidentally left open when you turn on the furnace, it will trigger a safety switch that prevents your furnace from turning on. To fix this issue, check if all furnace doors are closed securely and put back in place before turning on the system.

Restrictive air filter sadly also contributes to this problem. Some high-end and high-cost filters claim to be extremely efficient at catching allergens, viruses, and other bad guys in the air but become too restrictive for the system's proper amount of airflow. This can lead to a clogged air filter or even completely blocked restricting how much air can pass through which can cause overheating and system shutdowns. It's best to use a simple filter or a high-efficiency filter with a current rating standard sold today and recommended by good contractors instead of what big box store acts as "the latest and greatest."

1. Leave a Comment

"Leave a Comment" on the article about "furnace not working simple fixes" if you've ever been stuck in the cold with a broken furnace. Don't panic - there are several simple fixes that can save you time and money. From checking your thermostat to replacing your filter, this article will provide you with the tools you need to troubleshoot your furnace and get it up and running again.

Make Sure the Chimney Exhaust Flue Is Clear

One of the simplest reasons why a furnace may not be working is because of a blocked chimney exhaust flue. This happens when debris, such as leaves or birds' nests, accumulates and blocks the airflow. When this happens, the furnace's safety switch shuts down the system to prevent carbon monoxide from entering your home. Luckily, clearing out the chimney exhaust flue is an easy fix that will bring back warmth to your home.

According to Family Handyman, to clear out the chimney exhaust flue, turn off the furnace and climb on top of your roof with a flashlight and a broom. Use the broom to remove any debris blocking the flue's opening, making sure that it's completely clear before turning on your furnace again. By taking these simple steps, you'll ensure that warm air is flowing smoothly through your home without any interruptions caused by a blocked chimney exhaust flue.

Ensure Safety by Verifying Breaker and Shut Off Controls

Verifying the breaker switch and shut off controls of your furnace is essential to ensure safety. It sounds unbelievable, but sometimes a simple flick of a standard wall switch or resetting a circuit breaker can fix the problem. However, before you do anything, make sure to turn off the power supply to the furnace by locating the main electrical panel and flipping the appropriate circuit breaker. Once that's done, you can remove the front panel covering and locate the blower motor push-in switch. Make sure it's fully depressed before turning on the power supply again.

Discover How to Detect Leaky Ducts and Avoid Blockages

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If your furnace isn't working, one of the potential culprits is a leaky duct. So, how do you detect and avoid them? First, check the room registers to make sure they're open and unobstructed. Then, inspect the ductwork for any visible leaks or damage.

To seal sections of ductwork that may be leaking, use special metal duct tape (don't use regular tape as it won't hold up over time). Pay particular attention to branching points where multiple pieces of duct meet - these are common areas for leaks. Also, make sure all handles protruding from the ducts are tightly secured.

According to Family Handyman, "a typical house loses 20% to 30% of its air through leaks in the ductwork." Avoid this wasteful and costly problem by regularly checking your ducts for leaks and blockages. With proper maintenance and sealing techniques, you can ensure that your furnace is working efficiently and effectively for many winters to come.

Change the Furnace Filter

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One of the most common causes of furnace problems is dust and soot buildup in the heat exchanger, reducing its efficiency and causing your house not to warm. This can be easily fixed by changing your furnace filter. Dirty filters are a common culprit of clogged furnace filters that can cause your heating system to malfunction.

The good news is, changing your dirty filter is an easy fix! Your owner's manual shows you how to change inexpensive flat filters every month, make sure the arrow points towards the furnace. If you inspect pleated filters, they may last up to three months before needing replacement. However, if you have pets or kids that generate lots of dust and dirt, you may want to change them every month to ensure they stay clean.

If your furnace won't turn on at all, it could be due to a shutoff switch triggered by a dirty filter. Solution 2 from Family Handyman suggests turning off the power and checking for a switch near the furnace that might have been turned off accidentally. Changing your furnace filter regularly can save you time and money in repairs while keeping you and your family warm all winter long!

Frequently Asked Questions

Why is my furnace blowing cold air?

Your furnace may be blowing cold air due to a variety of reasons, such as a malfunctioning thermostat, a clogged air filter, or a faulty pilot light. It is important to have your furnace inspected by a professional to determine the root cause of the issue and prevent further damage.

What are the most common problems that require gas furnace repair?

The most common problems that require gas furnace repair are issues with the ignition system, thermostat malfunctions, and dirty air filters. Regular maintenance can help prevent these problems from occurring.

What could be causing my heater to not work?

Possible answer: A malfunctioning heater can be caused by a variety of issues, such as a blown fuse, a faulty thermostat, an overheated motor, or a clogged filter. To determine the root cause and fix the problem, it's best to consult a licensed HVAC technician who can diagnose and repair your heating system safely and efficiently.

How do I troubleshoot my heater at home?

To troubleshoot your home heater, start by checking the thermostat settings and ensuring it's on. Next, check for any tripped circuit breakers or blown fuses. If those are all okay, then it may be an issue with the pilot light or ignition system and you may need to call a professional for repairs.

What happens if you reset the clock on a furnace?

Resetting the clock on a furnace may cause it to operate inefficiently or not work at all, as it may disrupt the programming and settings of the unit. It is best to avoid resetting the clock unless necessary, and consult a professional if any issues arise.

Joel Sims

Content Writer

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Joel Sims is a passionate writer who loves sharing his knowledge and experience with others. He has been writing for several years and has covered various topics, including technology, lifestyle, and health. Joel's writing style is engaging, informative, and easy to understand.

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