how to fix a bad thermocouplehow to fix a bad thermocouple

You can run into problems if you choose the wrong type of thermocouple . Absolutely you dont want that. Start the test by unscrewing the thermocouple from the gas valve. If youre uncomfortable performing this test yourself, be sure to call a licensed HVAC contractor who can help you. I took the meter apart, disassembled the jack, tightened the pressure on the spring contacts, and reassembled the whole thing. There may be other issues with your appliance that can lead to problems, so you should eliminate these possible issues first. In this task, youll need to heat the thermocouple. If the resistance measurement shows a dead short from pin to pin, check the thermocouple itself first. Wipe away any remaining dirt or soot on the thermocouple with a clean, dry cloth. How To Fix: Start with cleaning the thermocouple. How to Survive an Encounter with an Ostrich, Unlock expert answers by supporting wikiHow, https://www.familyhandyman.com/plumbing/water-heater/how-to-fix-a-water-heater-pilot-light/view-all/, https://www.bobvila.com/articles/furnace-troubleshooting-2/, https://www.familyhandyman.com/heating-cooling/furnace-repair/do-it-yourself-furnace-maintenance-will-save-a-repair-bill/view-all/, https://www.familyhandyman.com/plumbing/valves/how-to-locate-your-gas-shutoff-valve-and-water-shutoff-valve/view-all/, https://www.familyhandyman.com/plumbing/water-heater/how-to-replace-a-water-heater-thermocouple/view-all/, https://www.sensorsmag.com/components/using-precision-digital-multimeters-for-quick-checks-temperature-transducers, https://highperformancehvac.com/how-test-thermocouple-multi-meter/, https://heatinghelp.com/systems-help-center/thermocouple-testing-procedure/. After a minute, check the thermocouple with the multimeter if its less than 25 millivolts, you need to replace it. If the flame lights and goes out when you release the gas control knob after holding it in for the recommended 20 to 30 seconds, that's the sign of a thermocouple malfunction. Now that is working again, it shows about 15 ohms. Make sure that the wiring is protected with insulation and is not damaged or broken anywhere in the circuit. Then delicately drag out the thermocouple. 1 cause of pilot lights that won't stay lit is a worn-out thermocouple. If you begin to experience problems with the pilot lights on these appliances staying lit, you probably have a bad thermocouple. As it heats up, attach one lead of the meter to one side of the thermocouple. A good pilot light flame is blue. A burned out or broken thermocouple should be replaced. Mine showed about 0.1 ohms when it wasn't working. This is what a cheap K-type thermocouple looks like: Note that the wires to the thermocouple (the little metal ball at the end of the cable there in the upper left corner of the picture) are bare - they can easily be shorted by bending or twisting the wires. Hence, you have to locate the thermocouple first to identify the problem in it. Its because of the dirt build-up inside the igniter. A small electric current goes to the auto-igniter when the gas valve signals the gas to turn on. *** For Informational Purposes Only. Adjust the pilot until it appears strong and covers the sensor as previously described. It didnt have a display, and Im not sure it even had a temperature sensor. If you suspect other problems with your gas appliance, visit this article for more advice. drawings. Dennis is a retired firefighter with an extensive background in construction, home improvement, and remodeling. To operate correctly, a thermocouple requires the full heat from the pilot light. Get out of the house, leaving the door open, and call the gas company or the fire department immediately to report a leak. It will secure your own safety. *** As an Amazon Associate I may earn from qualifying purchases at no extra cost to you. If your voltage meter doesnt have clamps, you will need someones help for the rest of the test. Step 1. If youve got a few minutes to spare, stay with me! They will replace the thermocouple when they do this. So that it can produce an ample amount of electrical flow. Water Heater Maintenance: Extend Water Heater Life Step 2 Burner assembly Remove the burner assembly and detach the thermocouple. Sometimes youll notice tour appliances arent lighting or lighting sporadically. Replace the furnace access cover and test the furnace operation by changing the thermostat settings to make sure the furnace turns on and off properly. Gevorg holds a BS in Business Administration and Management from California State University-Northridge. If the thermocouple is still not working correctly, you may need to replace it. A thermocouple lasts for an average of 10 years, and you need to replace yours if there is too much rust on it. Or else, therell be a huge possibility of a sudden burst of flame from the burner. The thermocouple will sit so that the tip of the thermocouple is directly in the pilot lights flame. If it appears small and has an orange-yellow tinge, it may be too weak to heat the thermocouple. If you found your way here and managed to fix your thermocouple, leave a comment and let me know how yours was broken and how you fixed it. The likely problem, again, is an obstruction in the pilot tube. If you can't get the flame to light at all, and you're sure the gas is on, there's probably an obstruction in the pilot tube. Step 4: Under the bracket, screw the bracket nut over the tube. What should I do if my thermocouple is coated with a white powder? Pull the valve housing aside using your 13mm socket wrench. As mentioned before that this device will convert thermal energy to electrical energy. Note: Only clean an orifice with compressed air as drill bits and other abrasive items can enlarge the opening. Step 2: Locate your thermocouple. Once this check is done, turn the meter back to volts. The pilot should heat the top 7/8" of the thermocouple with a clean (blue) flame. There are all sorts of methods out there. To replace a thermocouple: Step 1: Unscrew the copper lead and the connection nut inside the threaded connection to the gas line. Be sure to turn off the power to the device before attempting to remove the thermocouple. Generally, thermocouples have no wire connections. By creating an account you agree to the Hunker, How to Change a Thermocouple on a Fireplace, How to Troubleshoot an Electronic Ignition for a Superior Gas Fireplace, Adjusting the Gas-to-Air Ratio on a Heat-N-Glow Fireplace. The idea is to make that sensor portion really hot. If the reading is less than 25 millimeters, it should be replaced. In that case, you have to replace a new thermocouple. On his retirement, he started a remodeling and home repair business, which he ran for several years. Often the thermocouple connection points are overlooked, but are critical for proper readings. Performing a few simple inspections and maintenance may solve your thermocouple problem without the need to install a new thermocouple. With it all reassembled, the meter was again showing the correct temperature. A thermocouple is a device that produces a small electric current when it is heated. Remove the thermopile wiring connector from the gas control. Others require that you push the gas valve in to open the valve to the pilot light. I know this is the first question that hits your mind. The main reason for the decalibration is that the wires can become chemically attacked, which effects the wire composition, mechanical properties of the material and ultimately the temperature readings. wikiHow is where trusted research and expert knowledge come together. It may have gotten crushed or one of the wires may have broken off. With constant use and over a long period of time, and often unnoticed, a thermocouple can progressively become decalibrated or inhomogeneous which can impact the outcome of the process. The pilot can go out for a number of other reasons, however, so if you're having trouble getting the pilot to stay lit, the thermocouple may not be at fault. Before jumping to the conclusion that the thermocouple is at fault, look at the pilot flame. The thermocouple can do this because, in its probe, it contains two different metals, and a voltage is generated when one of them is heated. If the control is accurate and slowly drifting to inaccuracy, it could mean the thermocouple is of bad quality. Stocking the largest selection of appliance parts, heating, plumbing, lighting, and janitorial supplies, AMRE ships almost anywhere in Canada within 24 - 48 hours. Your email address will not be published. Next, attach the leads from the multi-meter to the thermocouple: put one on the side of the thermocouple, and attach the other lead at the end of the thermocouple that sits in the pilot light. The plug end was indeed shorted. Take the two leads from the meter and touch themthe meter should read zero. Call Air Experts at919-480-2727or contact us online today to schedule furnace repair service! Attach the red probe to the thermocouple and the black probe to the body of the gas valve. Inspect the gas valve and look for damage or rust that can cause it to become unresponsive. Reading the voltage level is the last step to find out the real cause. Therefore, inspecting and testing your thermocouple should be part of your furnace maintenance. The thermocouple is a small electrical device, but it is a critical safety component on your furnace. Sometimes the sporadic movement of the thermocouple can also shake its position. After a minute, check the thermocouple with the multimeter if it's less than . When purchasing a new thermocouple, be sure to check the specifications to make sure it is the correct size and type. If the pilot lights but the flame goes out as soon as you release the button after holding it for 60 seconds, then the thermocouple is bad. Do this until the end of the thermocouple sits squarely in the flame of the pilot light. 1 millivolt is equal to 1/1000 of a volt. Sounds interesting? Another option is to call a heating repair person near you. How To Get Rid Of The Made In China Smell 7 Methods to Try! Gevorg Grigorian. I fiddled with it for a while, then figured it was time to order a new thermocouple. And the worst part is that you can have a bad thermocouple without even knowing. Here Ive shown a 5-step method to find out if your thermocouple is bad or not. Present coupon at time of service. A working thermocouple will produce a reading of 25 to 30 millimeters. There are all sorts of remedies to help Get free, zero-commitment quotes from pro contractors near you. document.getElementById( "ak_js_1" ).setAttribute( "value", ( new Date() ).getTime() ); How to Fix a Thermocouple on a Water Heater? Meanwhile, dont forget to maintain safety measures. Wait until your thermocouple properly generates heat. To replace the thermocouple, youll need to purchase a new one that is compatible with your device. I disconnected the wires from the plug pins, cleaned more fuzz out of the way, and untwisted the wires. I understand this seems quite confusing for you. link to Does Citronella Actually Help Keep Bugs Away? Your furnace pilot light should burn just fine if you have got all these steps right. You should hear a clicking sound as the igniter fires, and then the burner should light. Light the pilot light and wait while you watch the voltage meter. Unscrew the thermocouple from the gas valve and have a helper hold the gas control knob to keep the pilot burning. Next, take your meter and set it to ohms. The auto-igniter then creates an electric arc to the burner, igniting the gas. Mine showed pretty much zero ohms from pin to pin, so at least it wasnt an open circuit. Thank you.". Your Promotional Selection Has Been Applied! When a thermocouple fails in your control system, bad things happen. By creating an account you agree to the Hunker, How to Change a Thermocouple on a Fireplace. Turn the gas valve on the appliance to the Light Pilot setting. Make sure that the wiring is protected with insulation and is not damaged or broken anywhere in the circuit. How To Install A Thermocouple On A Water Heater. "How to Repair Major Appliances" You will need a wrench, multi-meter, and a flame source, like a candle or a lighter, to perform the test. By using our site, you agree to our. With over 12 years of experience, Gevorg specializes in residential and commercial appliance repairs as well as heating, ventilation, and air conditioning (HVAC) services. Cleaning the thermocouple is a pretty simple process but should only be done when the fireplace is turned off and is completely cool. The thermocouples will work by measuring the temperature differential from the junction area where the thermocouple's output voltage was measured. Remove the thermocouple by unscrewing the copper lead and connection nut (first) and then the bracket nuts. A) Make sure the thermocouple is free of soot, centered in the flame of the pilot light, and is screwed in tightly to the control valve. For the actual test, turn on your flame source, and place the tip of the thermocouple into the flame, leaving it there until it is quite hot. Put Everything Back Into Its Place 07. The only way for that to be possible (lower resistance at the plug than at the thermocouple) was for there to be a short in the wiring in the plug. By signing up you are agreeing to receive emails according to our privacy policy. If the igniter has a pilot hole, move a sewing needle carefully around inside the hole to loosen any trapped material. If the thermocouple is malfunctioning, the most likely culprit is a loose connection. Multiple connections should be avoided in order to improve accuracy. It might be broken, but theres a better than fair chance that it is just shorted out. Separate the thermocouple connector from the gas valve. If youre still unsure or dont have a working pilot light, test the thermocouple with a multimeter. The information on this website is for informational purposes only; it is deemed accurate but not guaranteed. To help you, I am leaving a list of the most effective voltmeters-. After about a minute, when you're sure the probe has gotten hot, place one lead on the shaft of the thermocouple and the other lead on the connector. I know its really hard to tell if it has started to malfunction or not. 30 July 2020. However, if you need a professional to do the job, you can pay $120 to $150. I recently bought a new soldering iron, and have been familiarizing myself with it and learning what temperature it takes to do what. All you need to do is scrape the thermocouple clean and then dry-wipe the residue. If your equipment calls for a J type, you will need to replace with a J type. Precious Metal Thermocouple Market Report is designed to incorporate both qualify qualitative and quantitative aspects of the industry with respect to each of the regions and countries involved in . Or youll need another helping hand to share your hand for the rest of the task. First, inspect the flame. The procedure for lighting a standing pilot always includes lighting the flame, then manually holding in the gas valve to keep the flame burning and give the thermocouple time to heat up. Yes, you can clean a thermocouple, but the task must be done with a light touch. Some panels have a screw on each side that needs to be removed and other panels lower on a hinge. Push the connection nut to the threaded connection where the copper lead connects to the gas line. An old toothbrush is a perfect tool for this job. Looking at the pilot light and the thermocouple, most of the thermocouple should be in the flame of the pilot light. Make sure the connection is clean and dry. You are looking for a few things. Although thermocouples are reliable, temperature measurement errors can occur for various reasons. A few simple maintenance steps could have your igniter up and running again quickly. When cheap crap breaks and ordering a replacement will take too long. Were committed to providing the world with free how-to resources, and even $1 helps us in our mission. Then, when the pilot is burning brightly, release the reset button. Therefore, its always wise to practice proper maintenance and upkeep of your appliances. Step 3: If the pilot flame won't stay lit after several tries, it should be adjusted by a professional. The device can get dislocated while cleaning or other maintenance. That was odd. Enjoy! If the furnace still doesn't stay lit after cleaning, then its best to install a new thermocouple.Watch more furnace repairs: https://www.youtube.com/playlist?list=PLCo9SMjkdWBwU5dJaopTR09W7U05fEOF5___________________________00:00 Intro00:28 How it Works01:11 What You'll Need01:21 Identify the Thermocouple01:56 Cleaning03:16 Relighting04:13 Thermocouple Replacement___________________________AMRE Supply provides homeowners, service contractors, and property management with the parts and knowledge needed to get the best performance out of any property. Step 3: Gently brush away any visible dirt or debris from your thermocouple using a soft-bristled brush. A time constant has been defined as the time required by a sensor to reach 63.2% of a step change in temperature under a specified set of conditions. Since no flame is required to burn all the time, auto-igniters are less expensive to operate. Lastly, observe the reading of the voltage meter. At the. When the flame is weak, boost up the flame to reach the device. "Very clear and simple drawings make it easy to learn the basics in a short time. Finally, put back the thermocouple inside the box. Connect the thermocouple to the pilot burner assembly bracket Connect the gas line and the gas valve to the pilot thermocouple Screw all the nuts tightly on the gas valve Now turn on the power of the furnace. Install The New Thermocouple 06. Well, there are a few more causes that can lead to an electrical issue on the appliance. If you suspect this is the problem instead of the thermocouple, call a professional. How To Replace Thermocouple On Gas Water Heater? Fortunately, repairing a thermocouple is a relatively simple process that requires minimal tools and a bit of patience. Both the bracket nut and the connection nut should be only a little tighter than if hand-tightened. The bare wires can get shorted just by bending them. After that, generate heat on the thermocouple. Older gas appliances may have pilot lights that provide instant ignition when the gas is turned on. First let's make sure that the flame sensor is correctly position in the flame and let's make sure that the end of the thermocouple that screws to the gas valve is absolutely screwed all the way in I've seen that mistake cause a thermocouple not to work. Turn On Gas Supply And Check for Leaks Many times the readings are not correct or work at all, due to interference from crimp on connectors, solder, wire insulation, or incorrect materials being used for the connections. This is a great option if you need help making the repairs or suspect your system has other problems, such as a faulty gas valve. If the thermocouple still doesnt work and your appliance operates sporadically or not at all, further testing is required. For more specific instructions on operating your multimeter, read the owners manual. A dirty thermocouple may affect the ability of the gas fireplace to ignite. If the reading is less than 25 millivolts, the thermocouple is bad and needs to be replaced. Like the other component parts in your furnace, the thermocouple can wear down over time, producing lower voltage than it should when heated. To correct either condition, turn the pilot adjustment screw slightly, as directed by the manufacturer. Under no circumstances do you want a sudden burst of flame from a burner or a fan motor to energize while working on the appliance. Remove the valve using your pliers. In our final section, we will conclude our discussion of repairing major appliances with a detailed examination of -- of course -- motors. It's possible to replace the thermocouple without removing the burner assembly, and many repair people do this. Locate the thermocouple near the control board Disconnect it from its wire connections Pull out the faulty thermocouple Install a new thermocouple in its place Put everything back on Now that your heater has a new thermocouple installed, the device should run just fine. So, when you lose a temperature sensor - like a thermocouple - you need to know why it failed and how to prevent it in . While checking the tip temperature of the fine tip while soldering an SOIC-8 part, the meter just up and quit measuring temperatures. Though you have cleaned the device with a soft hand. Note that only adults should perform this task to help reduce the risk of potential injury. Using a small pair of needle-nose pliers is a safe way to adjust the thermocouple clamp. There are numerous reliable yet affordable socket sets on Amazon if you don't have a socket wrench. Richmond Water Heater Thermocouple Replacement: The How-To Steps 01. Clean the threads of the connecting nut with a pencil eraser and re-tighten. {"smallUrl":"https:\/\/www.wikihow.com\/images\/thumb\/0\/04\/Test-a-Thermocouple-Step-1.jpg\/v4-460px-Test-a-Thermocouple-Step-1.jpg","bigUrl":"\/images\/thumb\/0\/04\/Test-a-Thermocouple-Step-1.jpg\/aid9649384-v4-728px-Test-a-Thermocouple-Step-1.jpg","smallWidth":460,"smallHeight":345,"bigWidth":728,"bigHeight":546,"licensing":"