So you’ve checked your pilot light and even reset it, but still, it wont stay lit. But, putting your wire legs in a temperature gradient is bad practice to begin with - solder or not. Let’s take a quick look at how you might troubleshoot and fix a furnace thermocouple. These additional junctions cause measurement errors. View Profile View Forum Posts View Forum Threads Regular Guest Join Date Apr 2012 Location chicago burbs Posts 76 Post Likes . How to Determine if a Fireplace Thermocouple Failed. Furnace Shutdown . My wife threatened calling a plumber to come fix the problem – there’s nothing like threatening to spend a bunch of money to get my attention! Incorrect readings may not be caught right away, which means that you could work through bad sensors and cause even more downtime to fix the issue. thermocouple to the ADC should be simple and symmetric to avoid unintentional thermocouple junctions. You have a bad thermocouple if the flame lights and goes out. To replace a thermocouple: Step 1: Unscrew the copper lead and the connection nut inside the threaded connection to the gas line. How do you know if you have a bad thermocouple? It's a Gas! I get tired of all the safety equipment because it causes more problems for me than fixes. Tagged: how to fix a bad thermocouple . I did a little research on “your hot water heater not working”, and I determined that there were two issues that were the most likely. You must change a bad thermocouple as soon as possible. They are a few dollars each (get a male and a female), and easy to use. Before attempting any repairs, it’s a good idea to inspect and test your furnace thermocouple. Clean the thermocouple.The thermocouple, after four to five years of usage, can accumulate dirt and insects.Lift the protective flame screen off the heater, unscrew the nut and pull out the thermocouple.With a water hose, rinse the inside of the thermocouple tube, let it air-dry, then … Homeowner decided to fix a thermocouple with solder and a drywall screw. Calibration of thermocouples requires specialized equipment. This means that if the thermocouple goes bad, there is no way of detecting if the pilot light is burning or not. Tube contamination signs- these may include things like cracks, discoloration, or pinholes. If the furnace has been running, wait 30 minutes for the thermocouple to cool completely. If this temperature is not being hit due to a weak flame from the pilot, the thermocouple will shut off the gas flow to the pilot and shutting down your furnace. It should also be touching the surrounding sensors such as the thermocouple and thermopile. F. ferenc5 New Member. When thermocouples wear out, the pilot light goes out, the burner won’t light, and you will have no hot water. How do you fix a bad thermocouple? Place the new thermocouple in the same place your old one sat and close up the fireplace to conduct a test. I've used those hundreds of times with no problems at all. And when the pilot light goes out, you will not have hot water supply in your plumbing system. The distance between sensor and instrument can … Can you fix a thermocouple? Turn off the shutoff valve to the gas line. As the thermocouple signal connects to the ADC integrated circuit, each step along the path can encounter several additional thermocouples. Because I knew my thermocouple was working fine (since the pilot light would stay lit), I decided to check the output of the thermopile to see how much electricity it was generating. Next unbolt the thermocouple from the gas valve, then light the pilot and hold in the control knob to keep it burning. Domestic appliances / Hob / Solutions. Oxygen in the environment reacts with the pure metal of the thermocouple, making the wires thinner and potentially more brittle: as the oxidation grows worse, it exposes more … Follow: Ultimi Articoli. 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. How to Know When the Thermostat Is Broken in a Fridge or Freezer. If the color of the flame turns yellow or red, it’s a sign of gas contamination. That said, why not just use a thermocouple connector? Another tech at my company found this. When the probe has gotten hot,(about 60 seconds) place one lead on the shaft of the thermocouple and the other lead on the connector. Thermocouples that don’t work are a problem, but thermocouples that provide misleading information can be even worse. Replacing a Thermocouple Shut off the gas and electrical power to the furnace. 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