Did you know that the burner flame sensor in your oil burner is a crucial component that can prevent gas leaks and even explosions? That’s right, this small but mighty device plays a vital role in ensuring the safety of your heating system. In this comprehensive guide, we’ll dive into the world of burner flame sensors, helping you understand their importance, how to troubleshoot common issues, and how to maintain them for optimal performance. So buckle up and get ready to become an expert on burner flame sensors!
A Short Summary…
- Burner flame sensors are critical components of oil burners that monitor for active flames and shut off gas flow.
- Regular cleaning, inspection, and replacement can help ensure safe and efficient operation of the sensor.
- Contacting an expert in burner flame sensors is recommended to maintain safety & efficiency.
Understanding Burner Flame Sensors
Burner flame sensors are essential components in oil burners, as they serve as the first line of defense against potential gas leaks and explosions. These nifty devices monitor and confirm whether a flame is burning within the unit, and will promptly shut off the gas flow if the sensor fails to detect an active flame.
In doing so, they protect not only your heating system, but also your home and family from the risk of carbon monoxide poisoning and other hazards.
Types of Flame Sensors
There are various types of flame sensors available in the market, with cad cell detectors and thermocouples being the most common. Cad cell detectors are photoconductive flame detectors that are often utilized with oil primary controls. They function by altering their electrical resistance in response to the amount of light present at the sensor, allowing them to accurately detect the presence of a flame.
The C554A cad cell flame detector, for instance, is compatible with a variety of waste oil furnaces and residential burners, ensuring optimal performance within the combustion chamber. When installing a cad cell flame detector, it is essential to follow the burner manufacturer’s instructions and connect it to the F-F terminals of the oil primary control.
And don’t forget to disconnect the power supply before installation to avoid any potential electrical shock or damage to the equipment.
Components of a Burner Flame Sensor
A burner flame sensor typically consists of two primary components: the sensor glass and the wiring. The sensor glass is a short, thin metallic rod that generates a small electrical current to detect the presence of a flame.
This current is then processed by the wiring, which typically consists of a photodiode, resistor, capacitor, potentiometer, and LM393 comparator in an integrated circuit. Together, these components work in harmony to ensure that your oil burner operates safely and efficiently.
Locating the Flame Sensor in Your Oil Burner
To troubleshoot or maintain your burner flame sensor, you first need to know where it’s located within your oil burner system. The flame sensor is usually located near the burner assembly. It appears as a small rod with porcelain enclosing its end connected to the burner.
Before you begin any work on your furnace, make sure to consult the owner’s manual for guidance on the specific type of sensor required for your unit.
Accessing the Burner Assembly
To access the burner assembly and locate the flame sensor, start by removing the furnace cover. This will expose the burner compartment, allowing you to visually inspect the components inside. If you need to remove the burner assembly itself, simply unscrew the mounting screws.
Should you require assistance or are unsure about any step, don’t hesitate to refer to the manufacturer’s guidelines or consult a qualified technician. Safety should always be your top priority.
Identifying the Flame Sensor
Once you’ve accessed the burner assembly, it’s time to identify the flame sensor. As mentioned earlier, it appears as a small rod with a porcelain covering at the end that attaches to the burner. It is positioned just outside the burner assembly and can be either straight or bent at a 45-degree or 90-degree angle.
Keep in mind that different furnace models may have slightly different flame sensor designs or placements, so it’s always a good idea to refer to your owner’s manual or manufacturer’s guidelines for specific information.
Common Flame Sensor Issues and Solutions
Now that you know where to find the flame sensor and what it looks like, let’s discuss some common issues that may arise with these devices and their respective solutions. Furnace malfunctioning and failure to ignite are often indicative of a faulty flame sensor.
In the following subsections, we’ll explore two common issues – dirty or damaged sensor glass and faulty cad cell wires – and provide guidance on how to address them.
Dirty or Damaged Sensor Glass
Dirty or damaged sensor glass can cause inaccurate temperature readings and difficulty initiating the burner flame. To address this issue, you’ll need to clean the metal rod of the flame sensor, taking care not to damage the ceramic tube. You can use an emery cloth or a soft cloth/brush and electrical contact cleaner to gently remove any dirt or debris from the sensor.
If, during the cleaning process, you find that the tip of the sensor is black or the component is misshapen or broken, it is advised to replace the part instead of trying to repair it.
Faulty Cad Cell Wires
Another common issue with burner flame sensors is faulty cad cell wires. The resistance reading of faulty wires is measured to be above 1600 ohms, yet not infinite. If you encounter thermal lockout while the burner is burning, this may also indicate defective cad cell wires.
In such cases, it’s essential to inspect the wires and connections for any signs of damage or wear, and replace them if necessary.
Testing and Replacing a Burner Flame Sensor
If you suspect that your burner flame sensor is not functioning properly, it’s important to test it before considering a replacement. In the following subsections, we’ll guide you through the process of testing and, if necessary, replacing your burner flame sensor.
Testing the Flame Sensor
To test your burner flame sensor, you can use a multimeter to take an ohm reading between neutral and the burner assembly/manifold. The reading should be within the range of 300 to 1000 ohms. If the ohm reading is not within this range, it’s likely that your burner flame sensor is faulty and needs to be replaced.
Before conducting any tests, ensure that the Cad Cell sensor glass is clean so that light can pass through it properly.
Replacing the Flame Sensor
If your flame sensor requires replacement, begin by disabling the electrical power and gas supply to the furnace. Next, remove the access cover in front of the furnace burners to expose the flame sensor. Loosen the retaining nut or screw and carefully remove the flame sensor from its position.
Replace the old sensor with a new one, ensuring that it is compatible with your furnace model. Once the new sensor is installed, reconnect the power and gas supply, and test the furnace to ensure proper operation.
Preventative Maintenance and Care for Your Flame Sensor
Proper maintenance and care of your burner flame sensor can significantly extend its lifespan and enhance the overall performance of your furnace. In this section, we’ll provide some tips on how to maintain your flame sensor, including regular cleaning and routine inspections.
Regular cleaning is important to ensure that the flame sensor is free of dust and debris.
Regular Cleaning
One of the most effective ways to maintain your flame sensor is to clean it regularly. The metal rod (not the ceramic tube) of the sensor can be cleaned with an emery cloth or a soft cloth/brush and electrical contact cleaner. It’s recommended to clean your flame sensor annually to optimize its longevity and ensure the efficient operation of your furnace.
By performing regular cleaning, you can prevent the buildup of dirt and debris that could otherwise impede the sensor’s ability to detect flames accurately.
Routine Inspections
In addition to regular cleaning, it’s essential to conduct routine inspections of your flame sensor to ensure its proper functioning. During these inspections, you should check the flame rod and wire for openness, inspect the insulator for cracks, and verify proper burner grounding and power polarity.
By performing regular inspections, you can identify potential issues before they escalate, ultimately prolonging the life of your flame sensor and maintaining the safety and efficiency of your heating system.
Contact an Expert in Burner Flame Sensors and Safety Controls
If you’re unsure about any aspect of working with your furnace or handling the gas line, it’s always best to contact an HVAC expert. They can provide further assistance and support in troubleshooting and maintaining your burner flame sensor and other safety controls.
Remember, safety should always be your top priority, and there’s no shame in seeking professional help when needed. By consulting an expert, you can ensure the proper functioning of your heating system and safeguard your home against potential heat-related hazards.
Summary
In conclusion, burner flame sensors play a crucial role in the safety and efficiency of your oil burner. Understanding their function, troubleshooting common issues, and performing regular maintenance can significantly extend their lifespan and keep your heating system running smoothly. Whether you’re testing, replacing, or maintaining your flame sensor, always prioritize safety, and don’t hesitate to contact an expert if you need assistance.
So, the next time you’re enjoying the warmth of your home during those cold winter months, remember the mighty flame sensor working tirelessly to keep you safe and comfortable. With proper care and attention, you can ensure its continued performance and protect your home from potential disasters.
Frequently Asked Questions
What happens when a flame sensor goes bad?
When your furnace’s flame sensor goes bad, the furnace won’t be able to detect when a flame is present and it will continue to produce combustible gas. This can cause hazardous gas build-up and potential fire hazards.
To prevent this, make sure to keep an eye on your flame sensor and replace it if necessary.
How do I know if my furnace flame sensor is bad?
If you notice any of the signs mentioned above, then your furnace flame sensor might be bad and should be inspected and replaced as necessary.
What does a flame sensor do?
A flame sensor is a safety device designed to detect whether your furnace is producing a flame and burning the gas it uses for energy. It does this by jutting out from the front of the burner, usually positioned on the opposite side of the ignitor. By monitoring for a flame, a flame sensor helps ensure your furnace operates safely.
The flame sensor is an important part of your furnace’s safety system. It helps to detect any potential problems with the furnace before they become serious. It also helps to reduce the risk of a fire or other dangerous situations.
What is the purpose of a burner flame sensor?
The purpose of a burner flame sensor is to ensure safe operation of heating systems by detecting the presence of a flame and preventing hazardous gas leaks or explosions.
It does this by monitoring the flame and sending a signal to the control system when the flame is detected. This signal is then used to control the flow of gas to the burner, ensuring that the flame is always present and that the system is functioning properly.
How do I locate the flame sensor in my oil burner?
To locate your flame sensor, start by removing the furnace cover and look for it just outside the burner assembly.
Jason McNutt, the founder of Industrial Combustion, LLC, brings over 10 years of experience as an industrial combustion service technician. With a strong background in HVAC and certifications in safety, including OSHA and Arch Flash, Jason ensures the highest standards in servicing combustion equipment. He holds NATE certifications for various heating systems and EPA Section 608 Universal Certification for refrigerant equipment. Jason remains up-to-date with NFPA86 Standards for Ovens and Furnaces, providing comprehensive expertise to his clients. Outside of work, he enjoys spending time outdoors, coaching his son's football team, and working on his Jeep and four-wheelers.
