Gas Water Heater Thermocouple Test

The thermocouple is a vital safety feature for many gas appliances.

Gas water heater thermocouple test.

For a basic test attempt to turn on the pilot light again. How to test a thermocouple. If the thermocouple is working you should be able to measure 30 to 40 millivolts of voltage at the connection end of the tube when the pilot flame is on. First shut off the gas valve on the water heater and the gas valve on the gas line near the heater.

When it stops working the furnace s pilot light also turns off. For testing a thermocouple you first have to remove it from the furnace water heater or gas appliance where it is installed. A gas water heater in boise baton rouge buffalo or boston uses a thermocouple that includes a probe attached to a copper tube that screws into a port on the gas valve. With the leads apart you will read infinity.

If you re still unsure or don t have a working pilot light test the thermocouple with a multimeter. Measure the current by using the multimeter device set on millivolts. 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. You can test this yourself using a multimeter but you may need a helper to keep the pilot flame burning while you do it.

Use a small flame source to test a thermocouple with a multimeter. Then unfasten the three nuts that hold the thermocouple and the two gas tubes to the valve. Here s how to test a suspected thermocouple in a gas operated water heater. 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.

Touch the two leads together from the meter and you should get a reading close to zero. The burner typically sits loosely or under clips in the burning chamber and just slides out. Finally now turn the meter to volts. Diy hot water heater repair.

A thermocouple uses the heat from a flame to produce a millivoltage that controls a gas valve. Multimeter thermocouple test procedure. Usually a lighter will suffice for the test. If the pilot light doesn t stay lit check the gas water heater thermocouple by keeping the pilot button depressed.

Once it is removed you will need a multimeter that needs to have the ability to read millivolts and a source of fire. 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. First remove the thermocouple. That is simply a test to check the meter for continuity.

Gas appliance thermocouples have a standard design. Secondly turn on the meter and set it to ohms.