Some while ago, many furnaces utilized a standing pilot light for running. The standing pilot light is a tiny gas flame that stays ignited all the time. It can come with a green light bulb in front so that you notice the green flicker from the outside of the unit.
Standing pilot lights aren’t always reliable and use energy from continuously burning gas. Nowadays, furnaces come with an electronic ignition system, which also presents a risk for failure. When no gas reaches the burner, your furnace won’t light.
Furnaces are complicated machines, and the features ensure reliable performance and pose a risk for malfunctioning. Sometimes, you may expect the house to be heated, only to realize that the furnace’s ignitor doesn’t ignite. Even if the cause isn’t always severe, you don’t need to call the professional right away. Sometimes, you can try fixing the problem on your own. Keep in mind that you have to be extra careful with your furnace, as gas-operated machines are always dangerous.
If your Ducane furnace doesn’t ignite, you should try the following actions. It will be cheaper to address the problem on your own, of course.
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Examine the circuit breakers
When your furnace doesn’t ignite, you should start by checking if there’s the power inside the house. Check several electronic outputs (the microwave or the fridge). Should they have the ability, then it’s only the furnace that isn’t running.
Always start with the easy fixes such as the power to the furnace. Take a look at the furnace’s circuit breaker and ensure that the switches are turned on. When the controls are in the off position, they may have tripped. Reverse them to On position and wait to see if the furnace starts running.
When the furnace’s switch trips again, something more serious could be the problem, so you will have to call an electrician.
Check the air filter
Furnaces today come with several safety issues for accurate and reliable performance. The air filter is one, and when it’s clogged, the furnace’s ignitor won’t ignite anymore. You need to check, clean, and replace the air filter any now and then reduce the risk of problems.
It’s only a matter of time until the filter will clog if not correctly maintained. Take a look at the filter when the furnace doesn’t ignite. If clogging is obvious, you should clean/replace the filter. When the furnace still doesn’t ignite, you will have to keep investigating.
Examine the drain pan
It’s not always the ignitor stopping the furnace from igniting. Several things can affect the proper functioning of the furnace, even if they’re not related.
When the drain pan isn’t correctly draining, the furnace will stop running correctly. With high-efficiency models with AFUE ratings over 90% (96G2V, 96G1E, 95G1E, 92G1E), condensation will drain into a pan. Later on, the water will be drained by a pump and switch. For various reasons, the drainage will stop, and standing water ends up in the drain pan. Therefore, the furnace won’t start operating for safety reasons (risk of overflowing). The ignitor won’t ignite, but it’s only for your safety.
You only need a pump to drain the standing water. When the problem persists, you may have to replace the pump, in which case you should hire a professional.
Examine the gas supply
Sometimes, issues with the gas supply could stop the furnace from igniting. You should examine the gas supply to your house to see if everything is running correctly. If you have other gas-operated appliances in the home, check to see if they’re running or not. If they’re also not operating, you may have a problem with the gas supply, which is why the ignitor won’t ignite.
Should the gas supply be adequate, the gas supply to your furnace could be the culprit. It\s, not a problem to solve on your own, so call a professional to diagnose and fix. A broken valve or something more severe could cause the issue.
When the electric current is too high in your house, the furnace won’t start for safety reasons. In case of a power surge, the ignitor could automatically burn out. If so, you will have to call the experts to measure the house’s electric current. They will also replace the burnt-out ignitor.
Examine the ignitor sensor
As we’ve mentioned, modern furnaces come with several safety features, and the ignitor sensor is one to name. The ignitor sensor will inform the furnace when turning on the gas supply is safe. The ignitor sensor may get dirty after some time, so it won’t be capable of sensing the flame anymore. If you suspect that a dirty ignitor sensor is a problem, you should carefully clean it.
Begin with turning off the power supply to the furnace. Continue with removing the screw holding the sensor, lifting out the sensor. It’s a very fragile element, so handle it carefully. After removing the sensor, use some fine-grit sandpaper for cleaning the sensor of dirt and grease. Wipe away any remaining dirt or dust with a clean paper towel when you’re done. Put the sensor back to its place and see if the furnace ignites or not.
Many of the furnace’s parts won’t last as long as the furnace and the ignitor is one. In time, the ignitor will lose functionality and stop running correctly. Your furnace won’t ignite if the ignitor is long overdue.
However, it’s only a professional able to tell if the ignitor is old or not. The technician will also know which size of replacement you need for the ignitor. When the ignitor is the wrong size, the voltage will be incorrect, so that failure will still occur.
When to call the expert?
If nothing works, you will have to call the professionals. Sometimes, you may aggravate the problem when you’re not taking the correct steps for fixing it. Even if it costs you more, you should call the professionals for investigation and repairs.
Modern furnaces are dependable but go through intense use (they stop and start all the time), so problems will still occur. When the furnace doesn’t ignite, you should try our tips and recommendations before calling the technician.