I have a Whirpool/Estate Model# TGDS680EQ3 gas dryer that heats initially, but then does not stay hot. After a few minutes it is cold inside. This is true on all settings. I have changed the timer switch and the upper thermostat, checked the lint filter lines for blockage, and everything seems fine. The thing starts up fine, then the heat just dies. Any suggestions? Thanks.

Basically look for lint everywhere. There might be a diagram on Parts & Accessories | Shop & Find Lawn & Garden, Appliance Parts at Sears Parts Direct | SearsPartsDirect.com from Sears to take a look at. Don''t underestimate critters clogging the exhaust duct or the exhaust duct on the outside failing to open. Pay particular attention to lint around any of the sensors.

If this comes out negative and a diagram exists, I'll see what else makes sense. The timer would not have done it.

The timer switch was shot anyway. I've checked, no lint. Door opens fine outside of house, plenty of cool air exhaust. I replaced the coils too (in case there are more than one set of coils, these are the black cylinders in the ignition chain). Seems to be working fine on high heat, low heat is a bit weak, but I think it will dry clothes now.