It’s very easy to change a thermocouple on a hot water tank. What we are going to do is we are going to loosen the nuts to the thermocouple, we’re going to loosen the nut to the burner too and also to the pilot tube. We are going to use an adjustable wrench with smooth teeth, that way we don’t do damage to the soft material. Once we loosen all three, we are going to pull out the whole burner assembly, once we pull out the burner assembly it’s easy to knock off all the rust and the deposits that built up.
What this will allow to happen is this will allow us to get a better flame also. Once we get the burner assembly out, we can then remove the thermocouple by just applying some pressure, there’s a fitting that holds it inside the bracket here. Putting in a new theremocouple it’s very easy, all we do is take a new thermocouple, we push it back into the bracket and there is usually some type of compression fitting that holds it. If it doesn’t have a compression fitting, some have a nut that pulls up and you put it in place like that.
But most will have a very simple compression type fitting, so it’s very easy to put a new thermocouple in place. Most thermocouples can be any length that really doesn’t matter if you excess, you can just curl it up and leave it in place like this. Putting in the burner assembly, what we are going to do is put it back in, we are going to take all the tubes and we are going to put them back into the gas control, like so and then we are going to take the nuts and screw them back in place.
Again, we are going to want to hand tighten them, because it’s very soft material. One we tighten them up, we are going to put another quarter turn or so on with our wrench and once they are tight, we are going to turn on the main gas valve to the gas control. One we have the main gas filled on, we are going to turn the knob to pilot, we’re going to press down pilot and hold the flame to the end of the burner tube and at the end of the pilot tube. Once to pilot lights, we are going to continue to hold down this pilot for about thirty seconds, to warm up the thermocouple.
Once the thermocouple is warmed up, it’s going to send a signal to gas control that it’s on, once the gas control is released, the knob is released, we turn it to “on” and it’s going to allow a flow of gas to the burner. Once the burner is sucking gas, what we want to do is we want to test these three areas on the gas control that we screwed down our nuts and we are going to put a solution of water with a little bit of soup in it and if there is any type of gas leak, it’s going to blow bubbles. And that’s pretty straightforward and that’s how we change a thermocouple.