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Can I replace a thermocouple myself?
1 cause of pilot lights that won’t stay lit is a worn-out thermocouple. It’s easy to replace and a new one costs $5 to $10. Then detach the thermocouple from the burner and take it with you to the home center or hardware store to ensure you buy the right replacement.
How much should a plumber charge to replace a thermocouple?
Thermocouple – $20 to $150 The thermocouple is an apparatus that senses whether the pilot light is lit and triggers the gas control valve. Repairs typically cost about $150 to have it done professionally, though a new thermocouple itself only costs about $20 on average.
How do I know if my thermocouple is bad on my water heater?
A worn out thermocouple is one of the most common gas water heater problems. When thermocouples wear out, the pilot light goes out, the burner won’t light, and you will have no hot water.
Are thermocouples universal?
Honeywell, White Rodgers, and other manufacturers make universal replacement thermocouples, usually with a 30-millivolts (mV) rating for standing-pilot furnaces. Electronic flame sensors are much less universal, and you must find the exact part specified for your furnace model.
Are water heater thermocouples universal?
Universal Thermocouples. Universal thermocouples, as the name implies work on most water heaters. They are available online and in home supply stores for a reasonable cost. The length and the thread type are the two concerns when purchasing one.
Where is a thermocouple located on a hot water heater?
The thermocouple is part of the water heater’s burner assembly and is positioned next to the pilot light. It slides into a bracket and is held in place by a couple of clips. The thermocouple line runs outside the heater and is connected to the gas control valve, which is located on the outside of the tank.
What causes thermocouple to fail?
METAL FATIGUE Like everything, thermocouples can’t stay new forever. Changes in temperature can cause regular expansion and contraction in metal, which will cause thermocouples to weaken over time. After enough time, metal fatigue can cause a thermocouple to break.
How long does it take to replace a thermocouple?
Thermocouples are designed to detect a pilot light’s loss of heat and close the gas valve to prevent a gas leak. Replacing a thermocouple is a relatively easy fix that can take less than two hours.
How do you troubleshoot a thermocouple?
Importantly, always make sure the tip of the thermocouple is directly in the pilot flame. If the tip is in the flame, you have held the nob on the gas valve down for longer than a minute, the pilot flame is strong and steady, and the pilot still does not stay lit, then you likely have a problem with the gas valve.
What happens when thermocouple goes bad?
Normally when the thermocouple malfunctions or isn’t working, it simply shuts off the gas to your heater. This is important, particularly if the pilot light is out, because it prevents harmful gas from leaking into your home.
Are furnace and water heater thermocouples the same?
While most furnaces and boilers have a thermocouple, in some boilers and gravity furnaces a thermopile (pilot generator) will generate electricity to operate the gas control valve. You can distinguish this device from the metal tube of a thermocouple by the two wires in sheathing that lead to it.
Can I use any thermocouple?
Watch out: thermopiles and thermocouples are not interchangeable. When replacing a temperature sensing device like a thermocouple or thermopile, you should be sure to purchase the proper part.
How do I know what kind of thermocouple I need?
A thermocouple should exhibit very low resistance. Attach the negative lead to the red wire, and the positive lead to the yellow. In this case, the reading will be about three ohms. Thus we can conclude that this sensor is a thermocouple.
Why does my pilot light keep going out after replacing thermocouple?
If your water heater pilot won’t stay lit even after replacing the thermocouple, you most likely have a faulty gas control valve. It is a sign that the valve is failing to open and allow gas to flow to the pilot. You could also be dealing with a tripped or faulty thermal switch.
How do I clean the thermocouple on my gas logs?
How to Clean the Thermocouple in a Gas Fireplace Turn off the fireplace gas valve and remove the front panel from the fireplace. Find the thermocouple, which is located next to the pilot light and looks like a small straight pipe. Use a can of compressed air to gently blow away any dust and dirt from the thermocouple.
Do all gas water heaters have thermocouples?
Not all gas water heaters have a thermocouple. Some newer models have an advanced temperature control system. Essentially, it is a microprocessor that constantly monitors and controls burner operation and maintains consistent and accurate water temperature levels. The flashing LED indicates that the pilot is on.
How much does it cost to replace a thermocouple on a water heater?
The cost to replace the thermocouple on a water heater is $100 to $325. The thermocouple detects whether the pilot light is lit and signals the gas control valve to turn on the gas flow. Thermocouple replacement is the most common repair needed for gas tank water heaters.
Can you clean a thermocouple?
Yes, you can clean a thermocouple, but the task must be done with a light touch. Remove the thermocouple from the process assembly, using a steel wool or emery cloth, lightly clean the tip removing any build up.
Should thermocouple be in pilot flame?
The pilot flame should touch the thermocouple at a specific level. If the flame is blue and weak, and barely reaches the thermocouple, it needs to be stronger. If it extends well above the thermocouple, it’s too strong. Install a new thermocouple by screwing it in, heating it up a bit, and then lighting the pilot.
What is the most common thermocouple failure mode?
The most common failure mode for thermocouples is for them to fail open, this is known as thermocouple burnout. Burnout can result from a variety of reasons including the thermocouple experiencing a temperature in excess of that for which it was designed, metal fatigue, and oxidation.
How do I know if I need a new thermocouple?
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. 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.
Can you damage a thermocouple?
Like the other component parts in your furnace, the thermocouple can wear down over time, producing lower voltage than it should when heated. And the worst part is that you can have a bad thermocouple without even knowing. Therefore, inspecting and testing your thermocouple should be part of your furnace maintenance.
