Brand: Kenmore Model Number: 11078102310 Main Symptom: flame goes on for 7sec, off, comes on 1.5min later, and repeats What happens & when:
Error Code (if any): none
Parts or tests already tried: coil, igniter, flame sensor, High limit thermostat,
Thermal cut off fuse, Thermal fuse, cycle thermostat. All are fine.
Photos / video link:
Flame comes on for 7 sec, goes off, flame back on about 1.5 min, on for 7sec, goes off and repeats.
I have tested all the above and seems fine. I have replaced the coil and flame sensor to see if that was it but it wasn’t. I have removed the vent hose, just incase the vent hose was clogged and no change.
For this Kenmore 110.78102310 gas dryer, the burner should normally stay lit much longer than 7 seconds on a cold start. Since you’ve already checked/replaced the most common components (coils, igniter, flame sensor, thermostats, thermal fuse, high-limit, venting), we need to focus on what would make the flame shut off almost immediately and then wait about 90 seconds before trying again.
Most likely causes
1. Weak gas supply or gas valve/regulator issue
The igniter lights the flame, proving ignition is working. If the flame burns for only a few seconds and then drops out, the gas valve may not be maintaining proper gas flow even though the coils are new.
Check:
Gas shutoff valve fully open.
Flexible gas line not kinked.
Other gas appliances operating normally.
If LP propane, verify tank regulator pressure.
If possible, observe the flame:
Does it start strong and then gradually shrink before going out?
That points toward a gas supply/regulator issue.
Does it abruptly snap off?
More likely a control or sensing issue.
2. Cycling thermostat opening too early
You mentioned testing the cycling thermostat. How was it tested?
A thermostat can show continuity at room temperature yet still open at the wrong temperature. If the dryer temperature rises rapidly and the cycling thermostat opens after only a few seconds, you’ll get exactly this type of short burn cycle.
I would measure:
Exhaust temperature at the lint filter or outlet.
Watch what temperature is reached when the flame shuts off.
If the flame shuts off at a relatively low temperature, suspect the cycling thermostat despite continuity tests.
3. Thermistor problem (if equipped)
This model uses electronic controls and includes a thermistor in the exhaust housing. A thermistor that is out of calibration can cause the control board to think the dryer is hotter than it really is and shut the burner down prematurely.
A resistance check at room temperature compared to the tech sheet specifications would be worthwhile.
4. Control board issue
After all the components you’ve already tested, the electronic control becomes a realistic possibility.
The pattern:
Ignition works.
Flame established.
Burner shuts down after a repeatable short interval.
Waits a predictable amount of time and retries.
That can indicate the control is receiving an incorrect temperature signal or is incorrectly commanding the gas valve off.
A couple of questions that would narrow it down quickly:
When the flame goes out after 7 seconds, does the gas flame disappear while the igniter remains off, or does the igniter start glowing again immediately?
Are you seeing normal heat in the drum, or is the air only getting warm?
Did you replace the gas valve coils with OEM Whirlpool coils or an aftermarket kit?
Have you checked the thermistor resistance value at room temperature?
Those answers will help determine whether we’re dealing with a gas-valve problem, a temperature-sensing problem, or a control-board issue.