Maytag gas dryer igniter cycles on and off

[Patrick07]

Maytag gas dryer MDG9700A. The igniter and the gas cycles on and off every minute or so and only stays lit for about 15 secs. I have replaced the coils on the gas valve. The radient sensor has a resistance of .2 ohms. When I remove the thermostat it has continuity at room temperture. Resistance is .3ohms. The igniter seems to be working fine. Not sure what to check next.

[jeff1]

Hi,


The igniter and the gas cycles on and off every minute or so and only stays lit for about 15 secs

What was the original complaint?
Is this observed with any panel(s) removed? If being observed with a panel off the air flow could be poor allowing the heat chamber area to get too hot too quickly.
With the dryer together, same effect with and without the vent attached to the dryer?

jeff.

[Patrick07]

Hello Jeff,

Thanks for your reply. The original complaint was that the igniter and the gas cycles on and off every minute or so and only stays lit for about 15 secs. I first noticed this when I removed the back cover that holds the vent tube coming from inside the dryer cavity. To answer your questions, yes, this is observed with the front panel and the door removed. I will put the dryer back together and re-attach the vent and see if that solves the issue. I will post another reply with my results. I took the day off today to get this thing fixed!

[jeff1]

I will put the dryer back together and re-attach the vent and see if that solves the issue

Keep us posted.


yes, this is observed with the front panel and the door removed

Definetly will taint your results.
If similier all back together, try joining the 2 wires together on the safety thermostat ( on the heat tube ) as a test.

jeff.

[Patrick07]

Hello Jeff,

I put everything back together and I still get the same result - igniter and gas cycles on and off. I will take it apart again and join the 2 wires connected to the Hi temp safety thermostat together. My expected result is that the igniter and the gas will not cycle on and off anymore. Correct? If this is true, then the problem is my safety thermostat? Be right back, on my way to disassemble the dryer and connect the 2 wires together. I will post another reply with my results shortly.

[Patrick07]

Hello Jeff,

I tied the 2 wires together from the hi-temp thermostat located on the heat tube and the result was that the igniter and the gas did NOT cycle on or off anymore. Is this result telling me that my hi-temp thermostat is bad? Crossing my fingers here!

[jeff1]

Is this result telling me that my hi-temp thermostat is bad?

Recheck air flow ( filter, dryer ducts, fan blower wheel, exhaust venting, vent hood ) and yes it would be a good idea to replace the safety thermostat.

218 High limit thermostat, L230-50F Manufacturer Number 35001192 (http://www.repairclinic.com/referral.asp?R=153&N=1185514)

jeff.

[Patrick07]

Hello Jeff,

Thanks for the advice. I was able finally locate a high limit thermostat and I replaced it. The result is the same. The igniter and the gas cycle on or off. I rechecked airflow and the flow is strong and unimpeded. I removed all ducting from the outside of the dryer to verify the flow. Do you have any other suggestions for me? I am at a loss here.

[jeff1]

The igniter and the gas cycle on or off

They should. Exactly the same as before?....tested with and without clothes?


I rechecked airflow and the flow is strong and unimpeded

Where?

jeff.

[Patrick07]

Hello Jeff,

I get the same result with the new thermostat. I did not test the dryer with clothes in it. I will do this when I get home today. As far as the air flow is concerned, I disconnected the tubing from the back of the dryer and put my hand in the back of the machine to check the flow wtih the machine running. It is really strong. Is there a possibilty that it could be the radient (flame) sensor? Could the sensor be opening when it sees a flame and then closing prematurely? I tested the sensor and I have continuity but I have not checked it with a flame on it.

[jeff1]

Is there a possibilty that it could be the radient (flame) sensor? Could the sensor be opening when it sees a flame and then closing prematurely?

Flame sensor is suppose to open once the ignitor is hot enough. Once open the power has no choice but to go through the coil and open the gas valve.


I tied the 2 wires together from the hi-temp thermostat located on the heat tube and the result was that the igniter and the gas did NOT cycle on or off anymore.

For what ever reason the air is not going through the flame tube good enough to keep the flame from tripping the safety thermostat.


I disconnected the tubing from the back of the dryer and put my hand in the back of the machine to check the flow wtih the machine running. It is really strong.

Make sure the felt before the fan blower is sealing good, drum seals are ok as we don't want to sneak air in and out without it going past the flame.

jeff.

[Patrick07]

Hello Jeff,

We have success! I did what you said and before I went out and bought more parts I tested the dryer with clothes in it. That required me to put the WHOLE thing back together. I put some moist towels in the dryer and they ended up being dry within the allotted time! I kept checking the vent to see if I could feel the heat and there was heat there constantly. I realized that the dryer kept going on and off after I changed out the coils was beacuse the moisture sensor wasn't picking up any moisture and the dryer door was still off the unit. I know better now. Thank you for all your help and leading me in the right direction.

Patrick

[jeff1]

Glad all is better :)
Thankx for the update.

jeff.