My Gas Furnace Is Not Working – Now What? On old furnaces, the standing pilot light can go out due to a strong draft, a dirty orifice in the pilot burner, or dirt in the gas tube. By using The Spruce, you accept our, Review of Gas Furnace Types and Efficiencies, 3 Things to Check When Your Furnace Stops Working, How to Troubleshoot Electric Ignition Furnace Problems, How to Light the Standing Pilot Light on a Gas Furnace, Troubleshooting an Electronic Ignition Furnace That Won't Light, How to Replace a Furnace Thermocouple or Electronic Flame Sensor, How to Troubleshoot a Gas Furnace That Produces No Heat, Troubleshooting an Intermittent Pilot Ignition System, How to Check a Pilot Light on a Gas Furnace, Troubleshooting Common Problems With a Gas-Fired Hot Water Boiler. Either system can go bad over time and need repair or replacement, but sometimes the solution for a furnace not working is as easy as relighting the pilot light or replacing a thermocouple. Commercial Yearly Maintenance Sometimes, it is more stubborn. Some problems you can fix yourself, but it might save you money in the long run if you get a professional in right away. There are three types of thermostat systems used today: millivolt, low voltage, and line voltage.​ Make sure you have installed the correct type for your furnace. Then our idyllic reality is shattered and we want answers in a hurry. Once you do, you will be able to take stock of your options and pursue the strategy most likely to fix the issue cost-effectively. Or the thermocouple might be faulty, causing the gas supply to shut off. A gas furnace, regardless of its age, is still susceptible to problems, such as electronic ignition failure.Should this happen, the gas furnace ignitor will stop working, and the furnace will be useless. Here are a couple things to check before giving your local heating and air conditioning contractor a call. Your first step should be to determine where the water is coming from. Fortunately, problems with electronic ignitions sometimes can be fixed yourself. Like most home systems, furnaces that sit for long periods of time may have developed an issue when idle. Contact, © 2021 Global Heating & Air Conditioning | LIC #988444 | Powered by CNG Digital Marketing | Privacy Policy. It will likely lead to you needing to make a replacement. Gas leak. Some common symptoms exhibited by your furnace might actually be due to a faulty thermostat. Here are the top seven parts that, if defective, will likely prevent the furnace from heating, and all of them can be replaced by the average homeowner: Faulty Igniter – If the igniter is faulty, it will be unable to ignite the gas into a flame to create heat. Ignition Problems. Make sure the thermostat is switched to heat, the fan is on, and the temperature is adjusted to your target warmth. If it does not operate correctly, and you cannot troubleshoot the cause on your own, call a professional for home heating repair service. Gas leaks are dangerous. But otherwise, it could signal a problem with your furnace. The pilot light going out is one of the most common reasons that a gas furnace fails to produce heat. What Is a High-Temperature Limit Switch on a Furnace? Do not flip switches on the way out and do not stop to gather anything you find invaluable in the moment. Frequent cycling. 10 Easy Things to Check When Troubleshooting a Furnace Gas Valve. Not only is your home uncomfortable, but depending on the weather, it can also put your home at risk for bursting water pipes, mold and a host of other problems. I wanted to expand on our recent gas furnace troubleshooting series by going into each part of a furnace sequence of operation. A gas furnace should turn on and off throughout the day. ← Commercial Heater Installation: What to Expect, Pros and Cons of a Programmable Thermostat →. A high-efficiency condensing furnace is a little more complex than a conventional furnace, and troubleshooting is somewhat more complicated since there are more potential problems. The valve is closed when it is perpendicular to (or across) the gas line. 5 Common Problems With High-Efficiency Furnaces. With a gas furnace, the pilot light may have gone out or the gas valve may be shut off. Either system can go bad over time and need repair or replacement, but sometimes the solution for a furnace not working is as easy as relighting the pilot light or replacing a thermocouple. There are several possible causes to investigate, including a dirty filter, a blocked exhaust vent, or a faulty thermostat. Thermostats can be sensitive and when malfunctioning, can prevent your furnace from doing its job. The main gas line coming into your home may be off for some reason; a call to your gas company should alleviate this. If your Lennox gas furnace won't start, doesn't provide enough heat or continuously cycles on and off, a bit of troubleshooting might just solve the problem without ever having to get a repairman involved. Perhaps your blower motor has burnt out and you need a new one. You might hear loud banging, high-pitched squealing, or just a low-pitched humming. If you can spot problems with your gas furnace when they happen, you will be able to get the help you need to have your furnace fixed right away. High-efficiency furnaces are often known as condensing furnaces because they have a second heat exchanger that extracts additional heat from the air that passes through the first heat exchanger. Your thermostat may have been accidentally turned off, … (which may need resetting or replacing). The furnace doesn’t heat enough : In addition to a clogged filter, a furnace may not produce enough heat if it’s the wrong size for the space. If there is a reset button on your furnace, turn the valve to the pilot position and hold a flame to the dedicated pilot gas tube while pushing the button for about 30 seconds. Reasons for your gas furnace not working can be complicated or very simple. Most of the time it ends its hiatus without protest. If either the return or the vents are blocked, the furnace cannot do its job. If the breaker continues to trip, there may be an electrical problem with your furnace or your home’s wiring, which will require a professional to diagnose and repair. We have grown accustomed to warmth on demand. Electronic ignition occurs typically in one of two ways: intermittent pilot or hot-surface ignition. Another easy way to tell if the gas is on and working properly is by starting another gas burning appliance, like the stove. From a faulty thermostat to a dirty filter, there are several possible causes to investigate. Flip a switch or adjust a knob and within minutes, hot air bathes us in comfort; unless your gas furnace is not working. Modern furnaces come with safety switches on their front panels that don’t allow the furnace to engage if it’s not properly closed. First, confirm that the light is out. Browse Helpful Items on Amazon • Furnace Thermocouples • Thermostats • Furnace Filters • Furnace Motors Problems with a thermostat can manifest as a furnace that produces no heat, wild temperature swings, or a furnace cycling on and off too frequently. If your furnace is not working, you could end up facing a variety of problems. You might be able to address some repairs on your own while others will require a professional. Sorry about the poor camera work! Make sure there is power to your thermostat and that there is no dust or debris in its components. Sounds like a no-brainer, but if repairs or maintenance work were recently performed on your furnace, and it’s not working for some reason, you may want to check to ensure that it was turned back on. The most common reason for your furnace not igniting your burners is the failure of your pilot light. Furnaces and thermostats must be correctly matched to one another in order to function correctly. Since 2012, high-efficiency condensing furnaces with AFUE ratings of at least 90% have been increasingly popular, and they require different troubleshooting techniques. I’ll describe what the gas valve does and why it’s important. Fixing a gas furnace: this is a real-time look at how I'm keeping warm until the new gas valve comes. Step 1 Start with the basics. If the furnace still doesn’t work, be sure the thermostat isn’t faulty. 6. This can be very dangerous and should be addressed as soon as possible. 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