I worry that I've detoured away from the purpose of the forum, but, having this issue, I'm certainly willing to discuss it. ![:)]( "Smile")
The vented clothes dryers we have here in the US are not sophisticated. They raise the temperature inside the drum, and then vent the humid air outside (of the house). My dryer is gas-fired, so it has a burner and not an electric heating element.
So what happens is: There's a call for heat. The gas burner comes on within a chamber outside of the drum. That heated air is brought into the back of the drum and, hence, heats the air in the drum. At the front (near the door) of the drum the humid air is drawn through a lint screen (filter) and then vented to outside.
The dryer has two thermostats. A high-limit thermostat, which is used for safety, to prevent the heat from getting too high. The second thermostat is the cycling thermostat and is what is used to control the four heat settings (Low, Medium, Medium-High, High). The cycling thermostat has a typical heat sensitive switch, of course. But it also has (I think, but not confirmed) a heating element. The dryer heat setting determines how much "pre-heat" the cycling thermostat gets and, therefore, determines how much more heat the air in the drum needs to add to trigger the cycling thermostat. I've not found conclusive descriptions of this, but is what I've determined. But...The heat setting control knob only switches various resistors in series with the "heating element" of the cycling thermostat.
You might think, as I have, that the cycling thermostat is bad. But, no. It tests just fine and agrees with a new unit.
I don't know for a fact that my dryer is malfunctioning. But I've shrunk so many clothes that I'm suspicious. And, hence, the reason for me measuring the drum temperature....which appears to me to prove it so. Although, I now realize that I should have scaled the graph better.
The vented clothes dryers we have here in the US are not sophisticated. They raise the temperature inside the drum, and then vent the humid air outside (of the house). My dryer is gas-fired, so it has a burner and not an electric heating element.
So what happens is: There's a call for heat. The gas burner comes on within a chamber outside of the drum. That heated air is brought into the back of the drum and, hence, heats the air in the drum. At the front (near the door) of the drum the humid air is drawn through a lint screen (filter) and then vented to outside.
The dryer has two thermostats. A high-limit thermostat, which is used for safety, to prevent the heat from getting too high. The second thermostat is the cycling thermostat and is what is used to control the four heat settings (Low, Medium, Medium-High, High). The cycling thermostat has a typical heat sensitive switch, of course. But it also has (I think, but not confirmed) a heating element. The dryer heat setting determines how much "pre-heat" the cycling thermostat gets and, therefore, determines how much more heat the air in the drum needs to add to trigger the cycling thermostat. I've not found conclusive descriptions of this, but is what I've determined. But...The heat setting control knob only switches various resistors in series with the "heating element" of the cycling thermostat.
You might think, as I have, that the cycling thermostat is bad. But, no. It tests just fine and agrees with a new unit.
I don't know for a fact that my dryer is malfunctioning. But I've shrunk so many clothes that I'm suspicious. And, hence, the reason for me measuring the drum temperature....which appears to me to prove it so. Although, I now realize that I should have scaled the graph better.
Statistics: Posted by Mike**K — Sat Nov 30, 2024 12:22 pm