How Long Should A Thermocouple Last?

Why does my thermocouple keeps burning out?

It’s Dirty.

Soot buildup on the thermocouple may block the flame.

Under constant exposure to a hot flame, a thermocouple wears down over time.

Even a slight residue can make the thermocouple malfunction..

Can a thermocouple be cleaned?

The best way to clean your thermocouple is to use either a piece of steel wool or the coarse side of a sponge to gently clean off any soot or other remnants. You can use a pencil eraser to clean between the threads of the screw that connects the thermocouple to the control valve of your system.

Can you overheat a thermocouple?

If the back end of your thermocouple bulb gets constantly overheated, it will fail. With excessive back pressure coming from the burner ports, thermocouples can get burned up quickly.

Can you replace a thermocouple yourself?

It’s easy to replace and a new one costs $5 to $10. Rather than trying to unfasten the thermocouple inside the water heater’s burning chamber, it’s easier to remove the whole burner and thermocouple assembly. … Then unfasten the three nuts that hold the thermocouple and the two gas tubes to the valve.

Should a thermocouple be in the 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.

Do thermocouples wear out?

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.

When should a thermocouple be replaced?

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. If the reading is less than 25 millivolts, the thermocouple is bad and needs to be replaced.

How do you check if a thermocouple is working?

Place one test lead on the side of the thermocouple and the other to the end that screws into the gas valve. If the thermocouple has proper continuity, a small resistance reading should be visible on the multimeter. Many multimeters also indicate continuity with an audio alert.

Can you fix a thermocouple?

If the pilot remains lit, but the main furnace doesn’t stay lit, it’s time to replace the thermocouple. Replacement thermocouples are in stock at most hardware and home improvement stores. Because they come in different sizes, take your faulty thermocouple to the store with you so you can make a correct match.

Can you bypass a thermocouple?

So if you want to bypass the thermocouple you have to get rid of the spring mechanism. You can bypass the spring mechanism by simply using a screwdriver to pop out the little e-clip and take the valve off and problem solved.

What’s the difference between a thermopile and a thermocouple?

The main difference between Thermocouple and Thermopile is their method of measurement. The thermocouple is a thermoelectric instrument, while the thermopile is an instrument that modifies thermal energy into electrical output.

Are all thermocouples the same?

Simply put, the thermocouple or thermopile as they are sometimes called is a temperature sensor. … From an operational perspective the thermocouples for a water heater are all pretty much the same. However, there are two variables, the length and the fittings used to install them, see below.

Why do thermocouples go bad?

The presence of oxygen causes a reaction in the thermocouple that can wear down the part and make the wires become thinner and more brittle. Oxidation can be caused by a small amount of oxygen making its way into a sealed environment and reacting with the pure metal of the thermocouple.

How much does it cost to fix a thermocouple?

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.

Can a thermocouple work intermittently?

a safety device that has started to go bad, or has failed permanently. In this client’s case, the thermocouple was initially working intermittently, and then finally failed. … This allowed the gas to flow long enough to heat up the thermocouple and generate some electrical current flowing back to the gas valve.

Why does my pilot light keeps going out?

If the pilot light goes out, the thermocouple senses the drop in temperature and signals for the gas valve to close. If you have a faulty thermocouple is the most common reason that your pilot light is malfunctioning. Over time your water heater will collect dirt, dust and other kinds of debris.

What does a thermocouple look like?

The thermocouple looks like a piece of metal tubing smaller than a soda straw. To find it, first locate the gas control box. This is the box that the main gas line enters, where you turn the gas on in the furnace. (On most furnaces, it also houses the button that you hold open or push to relight the pilot.)

Does length of thermocouple matter?

The length of a thermocouple has no effect on its measurement accuracy or its ability to transfer the signal to the instrument. In other words, thermocouples do not experience “voltage drops” or power loss along its length as a high current power line might possess.

How does a thermocouple produce electricity?

By taking two strips of dissimilar metals which are the same size and joining them together at each end a loop is created. By making one of the joins in the metal very hot and the other join very cold, an electric current will flow through the loop creating an electric circuit.