Gas Dryer has heat at beginning of cycle then no heat.

Gas Dryer no heat: or shuts down soon after heating CHECK:

Thermal Fuse
If the air flow in the dryer is restricted, the temperature in the heating chamber can get hot enough to blow the thermal fuse. If the fuse blows, it cuts power to the coils that control the gas valve. The fuse is usually mounted to the exhaust duct just inside the back panel. You can check its continuity with an ohmmeter. If, after disconnecting the fuse, you get any reading other than 0 when you touch the leads of the meter to its terminals, it has blown. There's no way to restore it -- you'll have to install a replacement.

Igniter and Gas Valve Coils
TEST with a multi meter: The igniter is an electric conductor that works like the element in an electric heater, glowing hot enough to ignite gas when you turn on the dryer. This conductor can burn out, and when it does, it may glow, but it won't get hot enough to ignite the gas. At times it may give a reading of continuity yet fail mechanically and not get hot enough to ignite flame though it gets hot and glows and even may show Ohms or continuity ( close circuit) ?
Occasionally, the Gas safety valve and the electric coils that control the gas valve are defective -- they can wear out when the dryer gets old. When this happens, the igniter glows, but gas never enters the heating chamber or does not stay consistant.
Performing a continuity test on either part will help you determine whether or not you need to replace it. But the coils should also be tested for amount of resistance as well as Ohms. As they may be showing ohms yet not putting out enough resistance to keep proper gas pressure flowing. Most coils should show at least 1300 ohms ( GIVE OR TAKE 150 OHMS). Anything significantly less Thus u get an ignition but then it soon goes back out. The flame does not stay lit.

Air Flow and Heat
The motor that drives the tumbler also drives a fan that circulates air through the heating chamber and the tumbler and expels it through the vent. If the air can't circulate, perhaps because of lint blockage, the heating chamber overheats, which prompts the cycling thermostat to turn off the gas. The thermostat resets when the chamber cools, but the chamber heats up quickly and the thermostat again shuts off the gas. The result is that the temperature in the tumbler doesn't stay hot, and your clothes take longer to dry, if they get dry at all.

Warning
There's a big difference between a dryer that doesn't heat up at all and one that just doesn't get hot enough to dry your clothes. In the first instance, the problem is usually a defective part, and things should be back to normal after you replace it. In the second instance, the problem is caused by restricted air flow, and you need to clear the lint filter and vents and take steps to prevent lint build-up. If you don't, you'll use more energy for drying than you need and the dryer may continue to malfunction. Worse, you may have a dryer fire.

Hello,

While you didn't say im suspecting it a gas heated dryer??

If so here is whats wrong with it;
The reason your gas heated dryer starts off heating ok,but a part way through the cycle it is no longer heating as it did when it started,is beacuse the coils that open the gas valve are getting hot and breaking down when they are warm. At start up of cycle the coils are cool,but when the dryer heats up as it runs the coils that are weak can not handle the heat and do not open the gas valve. Replacing the gas valve coils with fresh,strong ones will open the gas valve the entire duration of the drying cycle. All appliance manufactures use the same exact gas valve coils and label them with their unique part number. Having been in the service business i know they are all the same and the part number for the least expensive gas valve coils is 279834
They can be purchased at your local appliance parts store on online at
searspartsdirect.com
repairclinic.com
apwagner.com
apdepot.com
midwestapplianceparts.com

To replace the coils,remove bracket over them(dont worry about where it says dont grip thats for when dryer is plugged in) unplug them and install new ones,that bracket has notches in it and the coils have tabs that inter lock so they position them self exactly where they fit.

This is what the coils looks like

Hi, If your dryer seems to run forever, it could be because of a clogged vent or internal ductwork. Your dryer may have an automatic cycle that turns off the dryer when the clothes are dry. It does this with a special thermostat or moisture-sensing system.
Normally, this is what happens during an automatic cycle: The thermostat tells the dryer to heat until the interior of the dryer reaches a pre-set temperature--say 135 degrees. When the dryer reaches the pre-set temperature, the thermostat tells the timer to begin advancing. (If there's a moisture sensor, the timer advances only if the moisture content of the clothing is low enough.) The timer advances until the interior cools, then the thermostat tells the timer to stop advancing, and tells the dryer to start heating again. This cycle continues until the clothes are dry. But if the vent is clogged, the dryer may never reach the proper operating temperature, so it doesn't send the signal to the timer and the dryer continues to run indefinitely, even if the clothes are completely dry. To fix the problem, clean the vent and/or internal ductwork.

Hi, If you have a gas dryer.
The most common problem with a gas and no heat is the ignitor going bad...

Here is a tip that I wrote about that problem...

Gas Dryer not Working Gas Dryer Not Heating
http://www.fixya.com/support/r4398592-gas_dryer_not_working_gas_dryer_not

If your dryer is electric..
There could be a number of different problems...
Check out this tip that I wrote about this problem...

Dryer Troubleshooting Electric Dryer won t Heat
http://www.fixya.com/support/r3866345-dryer_troubleshooting_electric_dryer_won

heatman101

the flame sencer window my need cleaning

Hi, You will need to change the coils on top of the gas valve. If the ignitor glows but the flame doesn't come on, this is your answer. It is a very common problem with the gas dryer. If I can assist you further, please let me know.
thanks
Vic

If your dryer seems to run forever, it could be because of a clogged vent or internal ductwork. Your dryer may have an automatic cycle that turns off the dryer when the clothes are dry. It does this with a special thermostat or moisture-sensing system.

Normally, this is what happens during an automatic cycle:

• The thermostat tells the dryer to heat until the interior of the dryer reaches a pre-set temperature--say 135 degrees.
  
  
• When the dryer reaches the pre-set temperature, the thermostat tells the timer to begin advancing. (If there's a moisture sensor, the timer advances only if the moisture content of the clothing is low enough.)
  
  
• The timer advances until the interior cools, then the thermostat tells the timer to stop advancing, and tells the dryer to start heating again.
  
  

This cycle continues until the clothes are dry. But…if the vent is clogged, the dryer may never reach the proper operating temperature, so it doesn't send the signal to the timer and the dryer continues to run indefinitely, even if the clothes are completely dry. To fix the problem, clean the vent and/or internal ductwork.

If your dryer seems to run forever, it could be because of a clogged vent or internal ductwork. Your dryer may have an automatic cycle that turns off the dryer when the clothes are dry. It does this with a special thermostat or moisture-sensing system.

Normally, this is what happens during an automatic cycle:

• The thermostat tells the dryer to heat until the interior of the dryer reaches a pre-set temperature--say 135 degrees.
  
  
• When the dryer reaches the pre-set temperature, the thermostat tells the timer to begin advancing. (If there's a moisture sensor, the timer advances only if the moisture content of the clothing is low enough.)
  
  
• The timer advances until the interior cools, then the thermostat tells the timer to stop advancing, and tells the dryer to start heating again.
  
  

This cycle continues until the clothes are dry. But…if the vent is clogged, the dryer may never reach the proper operating temperature, so it doesn't send the signal to the timer and the dryer continues to run indefinitely, even if the clothes are completely dry. To fix the problem, clean the vent and/or internal ductwork.

Never heard from you so called local repair service. Pros are best anyway.

If your dryer seems to run forever, it could be because of a clogged vent or internal ductwork. Your dryer may have an automatic cycle that turns off the dryer when the clothes are dry. It does this with a special thermostat or moisture-sensing system.

Normally, this is what happens during an automatic cycle:

• The thermostat tells the dryer to heat until the interior of the dryer reaches a pre-set temperature--say 135 degrees.
  
  
• When the dryer reaches the pre-set temperature, the thermostat tells the timer to begin advancing. (If there's a moisture sensor, the timer advances only if the moisture content of the clothing is low enough.)
  
  
• The timer advances until the interior cools, then the thermostat tells the timer to stop advancing, and tells the dryer to start heating again.
  
  

This cycle continues until the clothes are dry. But…if the vent is clogged, the dryer may never reach the proper operating temperature, so it doesn't send the signal to the timer and the dryer continues to run indefinitely, even if the clothes are completely dry. To fix the problem, clean the vent and/or internal ductwork.

if this helps please give me a fix ya vote