Kenmore 80 Series gas dryer starts with heat but very short time

Hello Friend, Your problem is very simple to fix. You're dryer needs a gas valve coil kit. To replace coils just remove front of dryer body and look below drum you will see the gas valve. The valve coils are located on top of valve (two little round black cylinders). It's simple, just remove the two screws from the little metal bracket that holds them down, unplug the wires from them and just lift them straight up off of the valve. Take notice that one has 3 wires and one has 2 wires. Just replace with new coils and plug wires back in and re-fasten metal bracket. Your dryer will run like new. Happy to help, Tim.

If gas is available after burner ignition for 3 - 10 seconds but then cuts out, this is an indication of a (1) lint clogged exhaust line,or (2) a fan suction bypass leak, both of which are resulting in insuffucient burner cone air/gas flow. Insufficient burner air flow results in actuating the high temperature limit thermostat or thermoswitch (usually a L220-40F thermostat) mounted on the topside of the cone. With inadequate cone air flow, burner flames are directed upward toward the thermostat instead of being pulled into the cone and then into the hot air supply for the dryer drum.
For (1), clear the exhaust line from the lint filter to the discharge louvers on the exterior of your home. Access to the backside of the dryer is necessary.
For (2), check the lint filter to fan suction connection for any possible leak paths. Access to the front interior of the dryer is necessary.
For a DG512, the front assembly that houses the lint filter and abuts the front end of the drum has a short duct that fits into the suction side of the casing for the squirrel-cage fan. This duct has a tendency to separate from the fan casing (its a slip fit) resulting in bypass leakage. If suction bypass leakage is occuring, this is air that is not being pulled through the drum, and hence, is not being pulled through the burner cone. As indicated above, a low cone air flow results in actuating the high limit thermostat, which then deenergizes the gas coils cutting of gas to the burner.
Note: These symptoms are NOT indicative of failed gas coils, since gas is being supplied initially to the burner for a period of 3 - 10 seconds. If the coil(s) have failed, the burner could not operate for any duration.