Where is the flame sensor located on a carrier furnace?


In terms of design, the flame sensor is a straightforward device that is situated at the burner assembly. Nothing more than a thin, generally bent metallic rod that rests in front of the flame stream within a furnace is required for its function. The flame sensor’s primary function is to provide confirmation to the system that, whenever the gas valve is opened, there is in fact a fire present.


In light of this, where exactly is the flame sensor located?

In your furnace, a furnace flame sensor is a highly fundamental component. Located on the burner assembly, it’s basically a thin metallic rod with a few holes in it. It’s generally bent, and it’s placed directly in front of the pilot flame in the furnace’s interior.


As a result, the question is: how can you get around the furnace’s flame sensor?

In fact, it is possible to circumvent the flame sensor. The flame sensor is just a means of exposing the voltage on the flame sensor wire to the flames produced by the furnace burners, and nothing more. Consequently, you may attach the flame sensor wire to a screwdriver and insert the screwdriver into the flames to detect heat.


How can I determine whether or not my furnace’s flame sensor is malfunctioning?

The following are signs of a faulty furnace flame sensor:

After only a few seconds of operation, the furnace goes out of commission (short cycles)

There is a break in the porcelain of the flame sensor’s housing.

Because of soot and corrosion, the flame sensor is no longer functional.


Is it true that every furnace is equipped with a flame sensor?

Not many furnaces are equipped with a flame sensor, but if yours is, it will be located close to the burner, with the metal rod positioned directly in the centre of the flame. Flame sensors are available in a variety of sizes (2 to 4 inches) and shapes (see examples below).


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What happens when a flame sensor stops working properly?

It is possible to tell whether a flame sensor is in poor working order since it will not detect a flame even when the furnace is operating correctly, and a flame sensor will immediately shut down the furnace unit. As a result, when the furnace is switched on, it will shut down rapidly and will not be able to provide enough heat to heat the whole home.


When should I get my flame sensor replaced?

Some expert technicians will replace the flame sensor if there is a problem with the flame current, while others may just clean the sensor when it is dirty. Others will replace them every two or three years as part of their preventive maintenance programme.


What is the best way to remove a flame sensor?

Turn off the gas and electrical power to the furnace, as well as the heat. Remove the lid that allows you to access the furnace. If the furnace has been operating for more than 30 minutes, turn it off and wait for the flame sensor to totally cool. It is important to confirm if the flame sensor is detachable; if it is, it should be secured to the burner assembly with one or more screws.


How much does it cost to replace a furnace flame sensor, and what does that include?

A new flame sensor may cost anywhere from $350 to as much as $500, depending on which furnace repair business you use. You will also be responsible for the cost of travel and diagnostics.


You may hear your furnace turn on, but it does not turn on or turn on properly.

The Pilot Light is a small light that serves as a guide for pilots (Faulty Ignition Sensor) When your furnace won’t ignite, the most typical problem is that the pilot light or ignition sensor is not working properly. Most of the time, this is the source of the issue when you hear your furnace turn on but it does not light up. It will be necessary to clear the sensor or ignitor if they are clogged.


What is the best way to read a flame sensor?

Put your metre (which can detect micro amps) in line between the flame sensor and the wire that was previously attached to it to get a reading on the signal produced by the flame (see picture). The flame sensor is most certainly unclean if you are reading anything less than 5 uA (micro amps) in any of your measurements.


Is it possible to clean a flame sensor?

Ensure that the Sensor is clean. Once the sensor has been removed, carefully massage the metal rod (just) with soft steel wool or a soft scotch brie type pad to remove any remaining residue. Never use sandpaper on the flame rod since it will cause harm to it. After that, use a clean paper towel to wipe away any dust that has accumulated.


What is the approximate cost of cleaning a flame sensor?

In most cases, the cost of cleaning the flame sensor is only the service call price, which means that at Cates Heating and Cooling, you may expect to spend $98 in total. Most customers find it simpler to begin with a service plan, in which a Cates expert will come out once a year to assess and conduct maintenance on their furnace.


What is causing the flame on my furnace to constantly going out?

Malfunctioning Thermocouple A faulty thermocouple in your gas furnace is likely to be the cause of your furnace’s pilot light failing repeatedly. When the thermocouple comes into direct touch with the flame in your system, it is called a thermocouple. When the pilot light is turned off, this component will disable the gas supply.


Approximately how long should the furnace’s flame remain on?

A word of caution about furnaces that have standing pilot lights: Once the pilot is lit, you must keep the button down for at least 30 seconds to ensure that the pilot remains lit (sometimes up to 1 minute). In this way, the flame has enough time to heat the flame sensor (thermocouple), which then signals to your furnace that it is safe to turn on the burner.


What is the operation of a flame sensor in a furnace?

When a fire occurs inside the furnace, the sensor is a short length of thin metallic rod that generates a little current of electricity in order to certify that a fire has occurred. With each opening of the gas valve, which signals the start of the combustion process, the sensor sends out a current, which is used to detect the existence of heat from the flame.


What is causing my furnace to not ignite?

if the furnace does not ignite when the thermostat calls for heat, it may be due to a malfunctioning control module, a malfunctioning pilot burner, a broken spark electrode, or weak connections between the control module and the furnace. To light the gas burner, the hot surface ignition system makes use of an electrical heating element to heat the surface of the burner.