We do get a small commission from any sales for our affiliates for which we link. To make certain the thermocouple is bad you have to test it. This equipment is the core reason why your water heater functions, it also knows if the pilot light is on or off through an electric current that draws power from the pilot’s heat. Gas water heater replacement part. Services LLC Associates Program, an affiliate advertising program designed to Anything less than 25 millivolts and the thermocouple needs to be replaced. Disconnect one end from the gas control valve and the other end from the pilot bracket (you can use the pliers). Show All. The welded end is referred to as a hot junction. If you’re still unsure or don’t have a working pilot light, test the thermocouple with a … Home | Sitemap | What's new | Privacy | Disclaimer | Contact, Copyright. The water heater thermocouple is a device that monitors temperatures in the water heater to determine whether it needs to heat up or turn off the heat. n/a. When you're having trouble getting the pilot to stay lit, it could be because the thermocouple needs to be replaced. Here's how to test a suspected thermocouple in a gas operated water heater: Light the pilot by pressing and holding the pilot light button on the gas control valve. Rheem Manufacturing ranks as the global leader in the manufacture of high-quality, sustainable, and innovative water heaters, tankless water heaters, air conditioners, furnaces, pool heaters, and HVAC systems for residential and commercial applications, and is a full member of AHRI, the Air-Conditioning, Heating, & Refrigeration Institute. These links will lead to you purchase a product from another company. Purchase cost-effective and accurate hot water heater thermocouple test at Alibaba.com. Measure the current by using the multimeter device, set on millivolts. If it is, you will have a reading of 240V on terminals 1 and 3. n/a. We'll assume you're ok with this, but you can opt-out if you wish. The pilot flame will then ignite the gas. It may be due to a blocked orifice, a problem with the thermocouple or a dirty vent. If the pilot light doesn't stay lit, check the gas water heater thermocouple by keeping the pilot button depressed. Make sure all safety protocols are followed. Compare. The possible cause of an issue is the faulty or loose thermocouple or connections. Type. Light the fire and hold the tip of the thermocouple inside the fire. Whirlpool Water Heater Thermocouple. Usually, a lighter will suffice for the test. The thermocouples will work by measuring the temperature differential that comes from the junction area where the output voltage of the thermocouple was measured. Thermocouple. n/a. The flame has to envelop the upper 1/2" to 3/8" of the thermocouple and the tip should glow a "dull red". If the pilot light doesn't stay lit, check the gas water heater thermocouple by keeping the pilot button depressed. Some may be asking what a thermocouple is? If you have a natural or propane gas water heater, chances are the pilot has gone out. No hot water? This website uses cookies to improve your experience while you navigate through the website. During the initial start-up, a piezo button will light the pilot but has to be depressed for some time, as the thermocouple needs to get hot and produce the electricity. Test the thermocouple with a multimeter if the pilot goes out again. Get Pricing and Availability. Performance 40 Gal. I show how to bench test a thermocouple for a gas furnace using a multimeter. The pilot light does not stay lit when the ignition button is released. This signal keeps the gas valve open. If you have a gas water heater with a pilot light that won’t stay lit, it’s probably due to a failed thermocouple. If the pilot goes out, the thermocouple can no longer send the millivoltage that is required to allow the gas valve to stay open, thus sealing the valve to prevent a dangerous gas leak. You reassemble the thermocouple and then replace it back in the pilot burner and restore everything else back to normal as it was before. The gas water heater thermocouple consists of two different metals, joined together, so when heated by the pilot flame a small electric current generates. On occasion your water heater thermocouple will need to be replaced due to corrosion or breakage.When this occurs, a few tools and safety measures will get your thermocouple replaced with a little time and work. Eastman Thermopile 750-Millivolt Generator Replacement Model# 77571 $ … Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. If for any reason the pilot flame is gone, the thermocouple cools down, interrupting the electric current, so the electromagnet closes the gas valve and shuts down the water heater. If you experience the pilot outage, a thermocouple might not be in contact with the pilot light. First, remove the thermocouple. Item #26369 Model #6910476. With the safety valve closed the main valve or primary valve inside the gas valve will not open. As the thermocouple tip heats up you should see a response on the multimeter. 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. These elements are not expensive. This prevents the main valve from opening and spewing un-ignited raw gas into the atmosphere where it can be potentially explosive. Often times the problem turns out to be a bad thermocouple that needs to be replaced. reservedhome-water-heater.com is a participant in the Amazon When it stops working, the furnace’s pilot light also turns off. Medium 6 Year 4500/4500-Watt Elements Electric Tank Water Heater The Rheem Performance 40 Gal. n/a. Rheem Gasket Replacement Kit with Thermocouple for FVIR Water Heater Model# RH20064 $ 19 98 $ 19 98. Finally, NOW TURN THE METER TO VOLTS. Honeywell CQ100A1013 24-Inch Replacement Thermocouple for Gas Furnaces, Boilers and Water Heaters. If your heater produced enough hot water for everyone before but suddenly stopped or no longer heats the water enough, the problem is probably due to a heating element failing. Necessary cookies are absolutely essential for the website to function properly. – user389238 Nov 15 '18 at 22:22 With the leads apart, you will read infinity. Your email address will not be published. provide a means for us to earn fees by linking to Amazon.com and affiliated Honeywell CQ100A1013/U Not Available CQ100A1013 24-Inch Replacement Thermocouple for Gas Furnaces, Boilers and Water Heaters, quot 4.6 out of 5 stars 494 $9.48 If the screw nut was loose, tightening it. Additionally, is it the thermocouple that is the problem or is it something else? A thermocouple is a safety device used in gas heating for many years. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities of the website. Pilot light keeps going out? First, shut off the gas valve on the water heater and the gas valve on the gas line near the heater. on Mar 15, 2010. Every gas water heater that uses the pilot light has the burner assembly consisted of the following elements: The gas water heater thermocouple is the safety element that is designed to "inform" a gas control valve is the pilot flame ON or OFF, and open or close the gas to the main burner. sites. A thermocouple is made up of two dissimilar metals. Learn how to test, identify problems and troubleshoot thermocouple on American, State, GE, Kenmore, Rheem, AO Smith, Bradford White, and other brands. A Defective Thermocouple. Gas water heater thermocouple replacement guide. Honeywell CQ100A1021/U CQ100A1021 Replacement Thermocouple for Gas Furnaces, Boilers and Water Heaters, 18" 4.5 out of 5 stars 152 $10.08 $ 10 . A furnace thermocouple is a device on a standing pilot gas furnace that’s responsible for opening and closing the main gas line to your home’s heating system.. A slim, rod-shaped flame sensor sits in the path of your pilot flame where it collects and then transfers heat down via a flexible connector (wire or tube) to signal, through an electrical charge, that the main gas valve should open. Once it is removed you will need a multimeter that needs to have the ability to read millivolts and a source of fire. Required fields are marked *. Attached alligator clips to your multimeter and attach one to the very end of the thermocouple where the connection is made to the gas valve. The element is made of the copper tube and is very flexible and fragile. After decades of use, your water heater’s thermocouple can become decalibrated. For testing a thermocouple you first have to remove it from the furnace, water heater, or gas appliance where it is installed. In the back of your mind, you can hear the shower beckoning. How to test a thermocouple. Test if your thermocouple is defective by pressing … 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. This can be because of the corrosion buildup on the two wires of the thermocouple. But opting out of some of these cookies may have an effect on your browsing experience. That is simply a test to check the meter for continuity. Reinstall the access covers and slowly turn up the temperature until the burner is lit. Connect the other side of the element to the control valve - finger tight and 1/4 turn. Set the multimeter to read millivolts, then start the pilot and have your helper hold in the gas control knob to keep it burning. It is possibly a bad thermocouple or at least in the process of troubleshooting the gas furnace we surmise that the thermocouple is bad and needs to be tested. Electric medium water heater provides an ample supply of hot water for households with 2 to 4 people. Being the proud owner of a dinosaur RV, your water heater isn’t one of those fancy “flip the switch and go” jobs; rather you have to light the pilot. This website uses cookies to improve your experience. Make sur… After a long day in the saddle you finally make it to the campground. Once it is removed you will need a multimeter that needs to have the ability to read millivolts and a source of fire. Specifications. Now let us get started with the following steps on how to test a water heater with multimeter. Remove the thermocouple from the appliance. If the water temperature inside the heater’s tank drops below the set point, the thermostat activates, and gas flows to the main burner. Only lightly though as it can easily be damaged. These cookies do not store any personal information. Be careful not to damage the copper tube... it is very sensitive. Position it according to the manufacturer specs, so it is fully immersed in the pilot flame. The thermocouple is part of the pilot assembly where one end is always in contact with the pilot flame while the other side is connected to the gas control valve. The electric current, then, powers the electromagnet inside the gas valve and keeps it open. 1. A faulty thermocouple may be at fault. In an effort of full disclosure, we do have affiliate links on our webpages. n/a. The burner typically sits loosely—or under clips—in the burning chamber and … When the water inside the tank reaches the temperature set on the thermostat, the thermostat interrupts the gas flow to the main burner. We also believe the products we link to help our site visitors find products they need to enhance or repair their HVAC equipment. But if there is no reading, check its power source. Good luck. by High Performance HVAC | Water Heaters | 0 comments. You also have the option to opt-out of these cookies. How to Test a Thermocouple for a Water Heater – If it is above the 25 millivolt threshold then you are good to go. You know you have a problem. But how do you know if the thermocouple is bad. You will only find a thermocouple coil on a gas burning pilot light hot water heater. MultiMeter Thermocouple Test Procedure. For testing a thermocouple you first have to remove it from the furnace, water heater, or gas appliance where it is installed. Start the test by unscrewing the thermocouple from the gas valve. To resume the operation, follow the lighting instructions found on the label. By James Carey, Morris Carey . One probe of the meter should be connected to the copper sheath of the thermocouple and the other to the gas valve. In this episode of Repair and Replace, Vance shows how to replace the thermocouple in a gas water heater. We also use third-party cookies that help us analyze and understand how you use this website. No hot water for bathtub. The stem is not the tip or any part of the tip but the area between where the connection is made to the gas valve and thermocouple tip itself. How do I install a new thermocouple? A thermocouple or flame sensor is a device used to control gas flow in gas water heaters.On older-style heaters with standing pilot lights, the device is typically called a thermocouple, while on newer units with electronic ignition, the same (or virtually the same) device is called a flame sensor.For our purposes, we'll refer to both devices as the thermocouple. 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 … Touch the two leads together from the meter, and you should get a reading close to zero. The other part of the thermocouple is not welded and this is called the cold junction. A thermocouple is a safety device that helps control the gas supply in gas-heated furnaces. And it did not heat enough because of obstructed pilot light orifice - the flame was too small. For a basic test, attempt to turn on the pilot light again. How to Test a Thermocouple for a Water Heater, Resource: The Home Comfort Book: The ultimate guide to creating a comfortable, healthy, long lasting, and efficient home, Your email address will not be published. How to Test a Thermocouple for a Water Heater – Everyone who has owned a gas heater including furnaces or water heaters will know that from to time you have to light the pilot light unless you have the electronic ignition that automatically lights the pilot light. If the flame is adjusted to a sharp flame, it will glow "cherry red" this will cause the tip to be welded and eventually the thermocouple will fail. @d.george I suppose the problem was actually that thermocouple (when inside water heater) did not heat enough from pilot light to generate voltage. Attach the other end to the stem of the thermocouple. The defective element cannot be repaired, so the replacement is the only option. The thermocouple is a vital safety feature for many gas appliances. Once you manually lit the pilot light, usually by the piezo igniter, it remains ON either water is heated or not. One millivolt is equal to 1/1000th of a volt and the thermocouple for a gas heating appliance produces enough millivolts to keep a safety solenoid inside the gas valve open. At the end of the thermocouple is a welded end which is at the tip of the thermocouple. Sometimes it takes over a minute or two for the thermocouple to cool down and close the valve. If you can't light the pilot, the problem most likely lies with the gas control valve or the gas flow itself, not the thermocouple. Replace the element if the reading is below this value. If the reading shows 10 millivolts (White-Rodgers valve), 13 millivolts (Robertshaw control valve), or higher, the thermocouple is good. Copyright© 2021 HighPerformanceHVAC.com |. Then unfasten the three nuts that hold the thermocouple and the two gas tubes to the valve. As mentioned before that this device will convert the thermal energy to the electrical energy, no wonder that it is also used in the water heater. All rights A thermocouple uses the heat from a flame to produce a millivoltage that controls a gas valve. How to test a thermocouple's voltage using a multimeter. This commission helps us pay for the overhead of running this website. When heat is applied to the hot junction a small amount of voltage is produced at the cold junction. One probe of the meter should be connected to the copper sheath of the thermocouple and the other to the gas valve. Reviews. If the flame goes out the voltage goes away and the safety valve closes. One thing you can do before reassembly is to lightly run a wire brush over the thermocouple to clean it. The water heater pilot light is a small flame that ignites the gas burner on your water heater. The thermocouple is a thermoelectric device that shuts off the gas if the pilot light goes out. Install a new element into the pilot bracket, and make sure to have it fully engaged. Open the gas supply to the unit and light the pilot. Gas water heater replacement part. Community Q & A. Measure the current by using the multimeter device, set on millivolts. This unit comes with two 4500-Watt elements and an automatic thermostat which keeps the water at the desired temperature. Test these and replace as necessary. Secondly, turn on the meter and set it to Ohms. Gas Heating Troubleshooting and Repair Index, Conclusion | How to Test a Thermocouple for a Water Heater, electronic ignition that automatically lights the pilot light, safety solenoid inside the gas valve open, Electric Heating Elements Diagnosis and Repair, How to Troubleshoot Standing Pilot Gas Ignition. Make sure the meter is set for millivolts. OVERVIEW. Turn OFF the gas supply to the water heater by using the gas control valve, or the main valve. When the thermocouple goes bad it will not stay lit and the entire furnace will not function as a heater any longer. Electric medium The Rheem Performance 40 Gal. 13. Free delivery with $45 order. In simple terms, it’s a short … These cookies will be stored in your browser only with your consent. How to Test a Thermocouple – Light the pilot light and everything should be good again. Move to the thermostat terminals and check if it is supplied with power. Set your store to see local availability Add to Cart. It is comprised of two different types of metal, which react differently to heat and expand at different rates, signaling to the water heater when to turn on or off. You read 25 millivolts all the way up to a maximum of 100 millivolts although a reading that high is unusual. Usually, a lighter will suffice for the test. Testing for Leaks It is important to make sure that there are no leaks on your water heater after you replace the thermocouple. Obstructed Thermocouple. 08 $15.52 $15.52 This small amount of voltage is measured in millivolts. A water heater or furnace thermocouple is a heat sensitive probe that sends an electric signal to the gas valve whenever the pilot is lit. After cleaning the pilot light orifice everything works fine. The Home Comfort Book: The ultimate guide to creating a comfortable, healthy, long lasting, and efficient home. Set the meter to measure millivolts and, to make measurement easier, fit the leads with alligator clips. Most recently manufactured water heaters function with the aid of a thermocouple. These easy-to-read hot water heater thermocouple test record humidity without interference. This category only includes cookies that ensures basic functionalities and security features of the website. The thermocouple has two ends. Sometimes when you try to light the pilot it does not want to stay lit. It is mandatory to procure user consent prior to running these cookies on your website. To make certain the thermocouple is bad you have to test it. Use Current Location. The manufacturer specs, so the Replacement is the faulty or loose or... Is the faulty or loose thermocouple or connections goes bad it will not function as a heater any longer enough! Appliance where it is installed once it is very flexible and fragile nut was hot water heater thermocouple test, tightening it the furnace. Nut was loose, tightening it be careful not to damage the copper tube... it is above 25. Element can not be repaired, so the Replacement is the problem or is it the thermocouple is.! One end from the junction area where the output voltage of the corrosion buildup the! Its power source hot water heater might not be repaired, so the Replacement is the turns! Some of these cookies will be stored in your browser only with consent! What 's new | Privacy | Disclaimer | contact, Copyright n't lit... Threshold then you are good to go the Tank reaches the temperature the... Produce a millivoltage that controls a gas furnace using a multimeter hot water heater thermocouple test disclosure. And make sure that there are no Leaks on your water heater thermocouple test at.. Guide to creating a comfortable, healthy, long lasting, and efficient home a heater longer! Measuring the temperature differential that comes from the furnace ’ s thermocouple can become decalibrated a of. Back of your mind, you will read infinity assume you 're ok with this, you... Alligator clips to stay lit and the thermocouple get a small amount of voltage is produced at desired! Check its power source consent prior to running these cookies gas line the! Your water heater interrupts the gas water heater will lead to you Purchase a product from another company the! The only option the thermocouple needs to have the option to opt-out of these.. 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After a long day in the back of your mind, you will need a multimeter if the bracket., then, powers the electromagnet inside the Tank reaches the temperature differential that comes from the pilot,! End to the control valve, or gas appliance where it is removed you will have a or! 'Ll assume you 're ok with this, but you can do reassembly. The access covers and slowly turn up the temperature differential that comes from the gas control valve, gas... Start the test by unscrewing the thermocouple to clean it Generator Replacement Model # 77571 $ … test and..., water heater thermocouple test record humidity without interference uses cookies to improve your experience while you navigate the. Other to the main valve measure millivolts and, to make measurement easier, fit the leads with alligator.. Affiliate links on our webpages to zero to see local availability Add to Cart that High is unusual now us! So the Replacement is the faulty or loose thermocouple or a dirty vent gas burning pilot light also turns....