Tip & How-To about Refrigerators

KNOWING ABOUT THERMOSTAT.

Normal 0 MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman";} What is a thermostat?
A thermostat is a device for regulating the temperature of a system so that the system's temperature is maintained near a desired set point temperature. The name is derived from the Greek words thermos "hot" and statos "a standing".
What is a dryer thermostat?
A dryer thermostat is usually oval shaped and about an inch and a half in length. The thermostat contains a bimetal that opens and closes a pair of contacts depending on the temperature inside the dryer. The bimetal inside the thermostat is designed to bend at specific temperatures. When the bimetal bends, it pushes an actuator. The actuator then pushes on a contact, opening the electrical circuit and breaking the electrical connection to the related component. When the thermostat cools, the bimetal returns to its original shape and the contacts close, allowing the current to flow through the circuit.
Have you ever thought about how hot your dryer gets? Thermostats and thermal fuses are put in dryers for your safety and if you don't maintain them, you could be putting yourself, your house, and your family at risk.
Your dryer uses of a combination of heat and airflow to dry your clothes. The heat generated in your dryer is produced by a heating element controlled by a series of thermostats. If any of your dryer's thermostats are defective, the results can be disastrous.
Here's how it works: The dryer is turned on and heat begins to radiate from the heating element into the dryer's drum. The air in the drum passes by a thermostat. As the thermostat reaches its maximum temperature, the bimetal bends, cutting the power to the heating element. The circuit stays open until the bimetal cools. Because the heating element isn't providing additional heat, the dryer's temperature gradually falls. The bimetal returns to its original shape and the electric current flows to start the heating element again. This process happens many times throughout your dryer's cycle.
There are at least two thermostats in your dryer: cycling (operating) thermostat and hi-limit safety) thermostat. The difference between these two thermostats is their opening and closing temperatures.
The cycling thermostat is typically found in the path of the air leaving the drum. A cycling thermostat is usually found on the fan housing or just under the lint filter area, on the blower wheel housing or inside the venting/exhaust system.
Some dryers may have as many as five thermostats - one for each of the different heat cycles. The temperature setting or cycle selected determines which thermostat is used to control the heat. If your dryer is malfunctioning on the low heat setting, the thermostat for that particular setting is probably defective.
The thermostats for the high and medium temperature selections are not the problem. However, if the dryer isn't working properly for most of the heat settings, it's probably a problem with your vent rather than the thermostats.
The hi-limit thermostat protects your dryer from overheating. This thermostat is usually found on the heating element, housing, or cage assembly. If the airflow in the dryer becomes obstructed by a plugged or improperly installed vent, bad drum seals, or a defective blower, the high-limit thermostat cuts power to the heating element. This means there are other problems with your dryer.
In conjunction with thermostats, dryers use thermal fuses as a safety device. Some dryer models may have two thermal fuses to detect extreme heat. If the hi-limit thermostat fails to cut power to the heating element and the element gets too hot, the thermal fuse blows and cuts all power to the dryer. This could mean that a thermostat is defective or something is wrong with your venting duct, filters, seals, or blower. You cannot reset thermal fuses so once they blow they must be replaced. Get the proper replacement fuse for your model and replace the hi-limit thermostat as well. Never bypass a thermal fuse.
Have a look at your dryer's manual for the locations of its thermostats. It's unusual for a dryer's thermostat to continue operating at a different temperature than originally intended and the only way to test for this would be by checking the temperature of the exhaust. You can do this by placing a pocket thermometer inside the exhaust vent. This test is done with the dryer running, so be extremely careful.
Checking continuity is another way to test your thermostat. There's a wire leading to each of the thermostat's terminals. The wires are connected by metal slip-on connectors. Label the wires before you remove them so that you're able to correctly reconnect them later. To remove the wires use needle nose pliers to pull on the connectors - don't pull on the wires themselves.
Set your multimeter to the RX1 setting. With the thermostat at room temperature, touch one meter probe to one terminal and touch the other meter probe to the other terminal. You should receive a reading of zero. If a thermostat is tested when it's heated to its limit, a reading of infinity should be produced. You should replace your thermostat if it fails either of these tests.
The thermostat is attached to the dryer with two screws. Remove both screws and discard the faulty thermostat. Install a new thermostat, securing it in place with two screws. Reconnect the two wires, put your dryer back together, and restore power to the dryer. Run your dryer through a cycle to make sure it's working properly.
Safety Warning: Before performing any tests or repairs on your dryer disconnect the power source to eliminate the risk of electric shock. You can do this by unplugging the dryer, removing the related fuse from the fuse box, or flipping the appropriate switch on the breaker panel.
For better protection of your family and yourself - maintain your dryer regularly. But if you can't do it yourself, make sure you contact a qualify service technician to do it for you. www.victorwod1234.blogspot.com

Posted by on

Refrigerators Logo

Related Topics:

Related Questions:

1 Answer

My Bush dryer is not heating up


The dryer Thermostat may have blown.
There are a couple of them:
The high limit thermostat is a safety device mounted on the heating chamber and is designed to prevent the dryer from overheating when the exhaust vent is restricted. A restricted vent will cause the high limit thermostat to trip or activate, interrupting the circuit to the heating element or gas valve. The high limit thermostat is not designed to activate repeatedly like a cycling thermostat and will eventually fail causing a no heat symptom. Disconnect the power to the dryer and check the thermostat for continuity with a multi-meter. If there is no continuity then it will need to be replaced and the restricted vent system corrected as well.
OR:
Cycling thermostats control the temperature inside the dryer drum. They are designed to "cycle" the heating element on and off to maintain the correct amount of heat. Cycling thermostats are normally located on the blower housing or elsewhere in the internal airflow ducting. Over time, the cycling thermostat can become defective. Disconnect the power to the dryer and check the thermostat for continuity with a multi-meter.

IT MAY ALSO BE THE TEMPERATURE SENSOR.
Temperature sensors are devices that change resistance depending on the temperature. The internal temperature of gas and electric dryers is managed by cycling thermostats on most dryers and by temperature sensors on some electronic controlled dryers. Depending on the dryer it may use multiple sensors to regulate the temperature. You can use a multi-meter to check the resistance of the temperature sensor. You will need to know what that resistance is at room temperature to verify if it is defective. This test should only be done when the power has been disconnected.
IF I HAD TO GUESS, I would bet it's one of the thermostats and I would start with checking these first.
Be aware that it could be many things that cause a dryer to not heat up such as the sensors named above or the timer could be faulty or the heating element itself is bad if it is an electric dryer, or if it's a gas model the ignitor or glow bar may be bad. But again I would start with checking the "fuses / thermostats" first.

Dec 01, 2013 | Dryers

1 Answer

need to know what obd code PO446 AND PO128 for a 2002 Daewoo Nubira means


P0128 - Coolant Thermostat (Coolant Temperature Below Thermostat Regulating Temperature)
This means that the engine's PCM detected that the engine has not reached the required temperature level within a specified amount of time after starting the engine. The intent of the P0128 code is to indicate a faulty thermostat. Similar codes: P0125

In determining the engine did not reach a "normal" temperature, it takes into account the length of time the vehicle has been running, the intake air temperature (IAT) sensor reading, the engine coolant temperature (ECT) sensor reading, and the speed of the vehicle.


P0446 - Evaporative Emission Control System Vent Control Circuit Malfunction
Evap vent valve has only one purpose. It closes in order to seal the vent so the EVAP system can pressurize and ensure there are no leaks. Evap vent valve is usually supplied Batt. voltage with key on. The ECM's driver controls the ground, and when grounded, activates the valve (closing it). If the ECM detects a short to ground, and open,or a short to battery voltage on the control circuit, P0446 will set. Code also may refer to ECM detecting that EVAP system is unable to achieve or maintain vacuum during test.


Hope this helps.

Sep 29, 2011 | 2002 Daewoo Nubira

1 Answer

what is the use of fan thermostat controller and explain about it?


A thermostat is a device for regulating the temperature of a system so that the system's temperature is maintained near a desired setpoint temperature. The name is derived from the Greek words thermos "hot" and statos "a standing". The thermostat does this by switching heating or cooling devices on or off, or regulating the flow of a heat transfer fluid as needed, to maintain the correct temperature.

Dec 23, 2010 | Black Box Fan Thermostat Controller Fan...

1 Answer

I have a theramador warming draw that has a thermastat,listed in the part discription, but there is no sensor device to regulate the temperature. Is it possible that the thermastat is actually a rheostat?The switch is a knobe you turn from off to low to higher temperatures.


Not exactly a rheostat, but a thermostat controlled switch similar to what you would find in an electric oven. It monitors temperature, and turns the heating element on and off to maintain.

The parts list at thermador-eshop.com show the heating element as p/n 101, and the sensor as p/n 102.

Your unit, with the rotary assembly, is the version before the electronic touch panel controls came out.

Jun 28, 2010 | Thermador WD27EB 27" Warming Drawer with...

Not finding what you are looking for?

358 people viewed this tip

Ask a Question

Usually answered in minutes!

Top Refrigerators Experts

Charles T Nevin
Charles T Nevin

Level 3 Expert

4066 Answers

John Tripp
John Tripp

Level 3 Expert

4654 Answers

yadayada
yadayada

Level 3 Expert

76630 Answers

Are you a Refrigerator Expert? Answer questions, earn points and help others

Answer questions

Loading...