Tip & How-To about Dryers

How heat on a gas dryer works.

Once the temperature drops the operating/control thermostat will close and complete the circuit to the gas valve assembly to cause the glow bar igniter to begin glowing until the flame sensor opens which causes the solenoid on the gas valve to energize and open the gas valve which will ignite from the glow bar igniter. If you find the glow bar igniter glowing and then fading back off with out any burner ignition would indicate weak solenoid coils on the gas valve and both coils will need to be replaced.so if you have no heat and when you start the dryer,listen to it,if you don't hear a click when it starts you have a bad thermal fuse and the igniter won't glow and all you have to do is check the thermal fuse with a meter,if you have heat at first and then no heat after a few minutes you have bad gas coils,the coils when they start to fail will work until they heat up then they won't open the gas valve and no flame,when they cool they will work again,if the igniter stays glowing but no flame the sensor is bad,and if the igniter doesn't glow check it with a meter for continuity,if open change it out.if the igniter glows and then goes out you still could have a bad gas coil,you'll have to check them with a meter,if they're good you either have a bad gas valve or the gas is off.if the gas is on when the igniter glows if you tap on the gas valve it could lite and sometimes when the valves are bad they chatter,or you might smell gas before the valve totally fails,hope this helps you out.

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I have a Kenmore Gas Wall Oven Model Number 911.30469894. When BAKE is selected, temperature shows 100 degrees and the oven never starts up or gets hot. BROIL works fine. Thank you, John


The oven control supplies voltage to the oven igniter/gas valve circuit. When the oven control is set to Bake, voltage is supplied to the oven igniter which should glow bright red to almost white hot. Once the igniter comes on and begins to glow it must pull enough current to cause the gas valve to open so the burner can ignite from the igniter. I added an image below with the theory of operation. Click this link:--http://media.fotki.com/1_p,swbbsqrsgstsqkkxgtqsskgwtqkq,vi/wrgtsbrktxwdfwfbgdg/1/1303472/5961857/image5576034710104836299img-or.png

----Open the broiler drawer and then set the oven control to bake and watch to see if the glow bar igniter glows or not. If it does not glow, the failure could be a broken Igniter, failed oven control board or gas valve. If the igniter is glowing red, then it can be possible that gas valve is faulty. To see how igniter looks. See the fig below:--

helpmech_69.jpg

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To order this part click the link below:--

http://www.repairclinic.com/PartDetail/Hot-Surface-Glow-Bar-Igniter/1990?modelNumber=911.30469894

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Also to confirm, check to see if the igniter is getting 120 volts when it's turned on. If it gets 120 volts, then your safety gas valve is bad because it's not letting the neutral go through. Otherwise, if it's NOT getting 120 volts, your control board shorted out and you need a new control board.
But as you mentioned that control board is replaced. So igniter should get 120 volts. If valve is faulty. But if igniter is not glowing then its faulty igniter confirmed.

To see how gas valve looks, please click the link below:---

http://www.repairclinic.com/PartDetail/Gas-Safety-Valve-Assembly/251898

In most of the cases the igniter is faulty, because gas valve getting faulty is very rare. But still getting the voltages checked, will confirm. These will help. Thanks. Helpmech.

Feb 04, 2011 | Kenmore 30464 / 30465 / 30469 Gas Single...

1 Answer

Glow bar starts, gas valve opens, gas start burning in all four ports, glow bar turns off and gas valve closes. no flame roll-out is it the board bad?


Depending upon how long the burners stay on it could be a bad or dirty flame rod, read on.
On a call for heat, the 24 volt thermostat sends a signal to the control module. The control module will indicate a call for heat with a light on the control either blinking or remain solid depending upon model. The inducer (exhaust) blower will purge all gasses from the furnace and pressurize a pressure switch. Once the pressure switch tells the module to continue, the electronic ignition will energize and send 120 volts to the igniter. The igniter will glow and you will be able to see it if viewed thru the small inspection port. Once the igniter gets hot enough, it sends a signal to the module opening up the gas valve (24 volts). Either a pilot will come on or the burner tube will ignite then spread the flame to all burners. Lastly a safety sensor will be looking for a certain temperature within a few seconds and the furnace will continue to operate and the room air blower will turn on in a minute or two.

What could go wrong? The unit will not run if there is no signal from the thermostat (bad thermostat or broken wire), the control module does not sense a signal from the thermostat (bad control), the inducer does not energize (bad motor), the pressure switch does not close (blocked vent piping, bad switch, plugged condensate hose), the igniter does not energize (bad control, bad igniter), the gas valve does not open or there is no gas (bad gas valve, broken wire, no gas), the pilot does not light (dirty pilot), the burner does not light (bad burner, plugged orifice, not enough combustion air), the flame does not spread to each burner (bad flame spreader, dirty flame spreader, more bad burners), the flame safety sensor does not detect flame (dirty or bad flame spreader, bad flame sensor, broken wire, bad control), or the room air blower does not energize (bad fan motor, bad control).

Jan 16, 2010 | Goodman Heating & Cooling

1 Answer

we have a 6 burner, nat gas cooktop....all unit light but the igniter clicking will not stop...unplugged it . question: all mechanics are closed is this safe gaswise?


What happens in this style ignition system is that the thermostat or electronic control switches power to the oven ignitor and gas valve circuit which are connected in series (one after the other). As power flows through the ignitor it heats and draws current (measured in amperage). Once the oven ignitor draws a specific amount of current the oven valve opens to allow gas to flow to the oven burner where the glowing hot ignitor (glow bar) ignites it. Power must continually flow through the ignitor and oven gas valve for gas to be released into the oven burner to create a flame. Once the set temperature is achieved the control stops all power to the ignition circuit which causes the ignitor to dim and the oven gas valve to close, stopping any burner flame. Cycling on and off continues to maintain the specific temperature the control is set for.

Jan 09, 2010 | Microwave Ovens

1 Answer

My dryer is GLGR341AS1, it works correctly but not dry clothes, along with not hot. Please if anyone can help me. A technician told me I needed to light the pilot, is this correct?


HI. The tech was not correct, in this case. Your unit dose not have a pilot. It is equipped with a Glow bar, for ignition purposes.

Most dryers have a thermal fuse, which burns out when the dryer overheats, in which case the dryer will either not run at all or stop heating. The fuse is usually located on the vent duct, inside the dryer. A blown fuse will show no continuity when measured with a meter. Before replacing the fuse, make sure the blower wheel is not broken or clogged, and there is nothing blocking the venting. If the fuse test proves that is is operational, move on to the thermostats.

The dryer uses multiple thermostats to regulate the temperature. When the temperature is higher than the preset limit of a particular thermostat, the thermostat breaks the circuit and the heater goes off. When the temperature cools enough, the thermostat closes the circuit again and the heat can come on.

Most dryers have a choice of temperature settings, therefore a separate thermostat is used for each setting. The selector switch or timer control then routes the circuit through the appropriate thermostat.

If a thermostat fails, it may prevent the heat from coming on, or cause long drying periods This happens because the thermostat does not close the circuit when the temperature falls below the operating temperature of the switch. It is a simple matter to test a thermostat; it should show continuity when the switch is cool and no continuity when it is warmer than its rated temperature.

A thermostat can also fail by being always on, no matter what the temperature. This switch would show continuity whether it was hot or cold. In this case, the heater would not shut off and the the dryer could dangerously overheat. As a safety precaution a second thermostat is used to cut-off the heater, or burner assembly when this occurs. This will be the thermal fuse, as stated above.

The thermostats are usually grouped together. The are typically oval in shape and about an inch and a half in size. They may be on the blower housing, under the lint trap or inside the vent line. There should be two wires connected to each thermostat.

Label the wires and connections so that you can properly reconnect them later. The wires are connected with slip on connectors. Firmly pull the connectors off of the terminals. You may need to use a pair of needle-nose pliers to remove the connectors. Inspect the connectors and the terminals for corrosion. If either is corroded they should be cleaned or replaced.

To test the thermostats or fuse, set the multimeter to the ohms setting X1. Touch one probe to each terminal. You should get a reading of either zero or infinity. At room temperature, the thermostats should have a reading of zero. When the thermostats are heated to their limit temperature, they should switch off and you should get a reading of infinity. The fuse should be tested at room temperature for continuity.


Now, if the thermostats are ok, and test out well, move on to the burner assembly, and ignitor test.


The easiest way to check the ignitor is to observe it. Remove the small access panel in front, select a high temperature setting and start the dryer. Watch the burner assembly, shortly after starting the unit the ignitor should begin to glow or spark. If you see it glow or spark, then the ignitor is working. If the ignitor did not appear to function and it is the spark type, it may be out of adjustment which generally requires professional service or it may require replacement. If the ignitor is the glow type, you can test it for resistance with a multimeter.


The ignitor has two wires connected to it.Label the wires and connections so that you can properly reconnect them later. The wires are connected with slip on connectors. Firmly pull the connectors off of the terminals (do not pull on the wire itself). You may need to use a pair of needle-nose pliers to remove the connectors. Inspect the connectors and the terminals for corrosion. If either is corroded they should be cleaned or replaced.

Set the multimeter to the ohms setting X1. Touch one probe to each terminal. You should get a reading anywhere between 50 and 600 ohms. If you get a reading of zero or infinity, the ignitor is definitely bad and will need to be replaced.

Ok, if the ignitor is ok, and functioning well, move on to the last area of concern. This will be the Burner assembly.



On the gas valve are one or two coils (solenoids) used to open and close the valve to control the flow of gas. If a coil fails, gas will not flow and the dryer will have no heat.

The easiest way to diagnose a problem in the burner assembly is to observe the burner operation. Remove the small access panel at the bottom, front of the dryer, select a high temperature setting and start the appliance. Watch the burner assembly, shortly after starting the dryer the ignitor should begin to glow. Next you should hear the click of the gas valve coil and a flame should ignite. The flame should be mostly blue and it should remain on for a minute or more.

If the ignitor glows for several seconds (up to 15 seconds) and then goes out, the problem is probably the coils (solenoids). If the ignitor glows and stays on, then the problem is usually the flame sensor. If it ignites and then quickly goes out, it is most likely a problem with inadequate air flow.Test the coil for resistance using a multimeter. Set the multimeter to the ohms setting X10. Place a probe on each terminal. The multimeter should change from a reading of infinity to roughly 1300 ohms (+/- 150 ohms) when the probes touch the terminals. If the reading is infinity or substantially different from 1300 ohms, the solenoid should be replaced.






Dec 28, 2009 | Frigidaire GLGR341AS Gas Dryer

1 Answer

maytag mdg 4000bww wont heat igniter lights burner turns on but stays on only for about 10-15 seconds is there a high limit problem? thanks in advance


On the gas valve, There are one or two coils (solenoids) used to open and close the valve to control the flow of gas. If a coil fails, gas will not flow and the dryer will have no heat.

The easiest way to diagnose a problem in the burner assembly is to observe the burner operation. Remove the small access panel at the bottom, front of the dryer, select a high temperature setting and start the appliance. Watch the burner assembly, shortly after starting the dryer the ignitor should begin to glow. Next you should hear the click of the gas valve coil and a flame should ignite. The flame should be mostly blue and it should remain on for a minute or more.

If the ignitor glows for several seconds (up to 15 seconds) and then goes out, the problem is probably the coils (solenoids). If the ignitor glows and stays on, then the problem is usually the flame sensor. If it ignites and then quickly goes out, it is most likely a problem with inadequate air flow.Test the coil for resistance using a multimeter. Set the multimeter to the ohms setting X10. Place a probe on each terminal. The multimeter should change from a reading of infinity to roughly 1300 ohms (+/- 150 ohms) when the probes touch the terminals. If the reading is infinity or substantially different from 1300 ohms, the solenoid should be replaced.

Additionally, The dryer uses multiple thermostats to regulate the temperature. When the temperature is higher than the preset limit of a particular thermostat, the thermostat breaks the circuit and the heater goes off. When the temperature cools enough, the thermostat closes the circuit again and the heat can come on.

Most dryers have a choice of temperature settings, therefore a separate thermostat is used for each setting. The selector switch or timer control then routes the circuit through the appropriate thermostat.

If a thermostat fails, it may prevent the heat from coming on, This happens because the thermostat does not close the circuit when the temperature falls below the operating temperature of the switch. It is a simple matter to test a thermostat; it should show continuity when the switch is cool and no continuity when it is warmer than its rated temperature.

A thermostat can also fail by being always on, no matter what the temperature. This switch would show continuity whether it was hot or cold. In this case, the heater would not shut off and the the dryer could dangerously overheat. As a safety precaution a second thermostat is used, This is called a thermal fuse. The power will be cut to the heating circuit if the maximum safe temperature is exceeded. In most cases, this is a one time fuse. The heater circuit will not function until the fuse has been replaced. Of course, it will be necessary to determine and repair the underlying cause of overheating or the fuse will just cut out again. The most common cause of overheating will be a clogged ventilation assembly. Be sure to inspect the entire ventilation Assembly for build up. This will cause issues, if obstructions exist.

The thermostats are usually grouped together. The are typically oval in shape and about an inch and a half in size. They may be on the blower housing, under the lint trap or inside the vent line. There should be two wires connected to each thermostat.

Label the wires and connections so that you can properly reconnect them later. The wires are connected with slip on connectors. Firmly pull the connectors off of the terminals. You may need to use a pair of needle-nose pliers to remove the connectors. Inspect the connectors and the terminals for corrosion. If either is corroded they should be cleaned or replaced.

To test the thermostats or fuse, set the multimeter to the ohms setting X1. Touch one probe to each terminal. You should get a reading of either zero or infinity. At room temperature, the thermostats should have a reading of zero. When the thermostats are heated to their limit temperature, they should switch off and you should get a reading of infinity. The fuse should be tested at room temperature for continuity.

Dec 16, 2009 | Maytag MDG4000 Dryer

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