Simple Series Circuit - Troubleshooting Appliance Problems

Today we're looking at just a simple series circuit. There is your L one and here is your L two, that’s all this is, the pilot indicator light, the indicator light here, is parallel with the heating element in this particular case, sometimes you will see pilot light going from L one over to neutral, that doesn’t matter, don’t worry about that, that doesn’t affect the operation of the element itself, your strategy, when you are dealing with this problem where the cooktop's element does not stay on fully and it seems to go out frequently, it’s not full on even though the switch is set to max and the element goes out periodically.

Your strategy first is to rule out, is it a problem with the infinite switch, all of these contacts here are physically on the infinite switch, that is what the knob is attached to, you will accomplish this by doing live testing between H two and L two, you are going to have one of your meter probes on H two, you will see it called  out there on the infinite switch, another one of your meter probes on L two, then actually it’s just fire in the hole, range plugged in, knobbed turned on and you are going to be looking for that voltage across H two and L two to be what?

Here is a pop quiz, you have voltage fired up, we are plugged in and if this switch is closed what should you read across H two to L two? Anybody? That’s right, you should read about zero or some fractional voltage which will just be your voltage drop across the closed contacts on that switch.

If you ever see two hundred and forty volts across H two to L two, the thermostatically controlled contacts, then you know that the infinite switch is opening, I am talking about when the switch is set on max-high, with that infinite switch set on max, high, ten, whatever it is, the maximum setting, H two to L two should always be closed, if it ever opens, then you know you have got an infinite switch that is failing under load.

Alright, so, I wanted to give you some fun facts to know and tell about these glass cooktop ribbon elements that have the thermal limiter built into them and, by the way, all glass cooktop ribbon elements will have a thermal limiter built into them, that thermal limiter in the element opens at about one thousand to eleven hundred degrees Fahrenheit.

The reason for this is to prevent glass cook wear that a customer may be using, which is formed at about fifteen hundred to seventeen hundred degrees Fahrenheit from fusing to the glass cooktop, ok, the glass cooktop is formed at about three thousand degrees Fahrenheit, it’s not going to melt or crack or affected by this thousand, eleven hundred degree Fahrenheit. Cook wear, particularly if it’s cheap glass cook wear could be affected by this so they want to cut if off well before any issue may arise from cheap glass cook wear that could melt just enough to fuse to the glass cooktop, that’s why those thermal limiters are in there.