Help! C Oven Pilot won't stay Lit

[Kitzig]

Ok, Miss Penny is up and running but we can't get the oven pilot to stay lit. We are on propane and the top burners are working just fine. We have a safety system that was installed at the factory. We hold down the red button, light the pilot, wait for it to burn for a little bit of time, then let go of the red button. The pilot goes out everytime. What are we doing wrong? [img]graemlins/cry.gif[/img]

Lori G,

[lowracer]

Is the flame enveloping the top 3/8" of the thermocouple? This is critical. The thermocouple generates the electrical current required to hold the safety valve open. It generates this current only when it is really HOT. It has to be bathed in flame, not just near it.

See photo for correct flame/thermocouple positioning:

[img]http://img224.imageshack.us/img224/8742/img18682qr.jpg[/img]

If your flame looks like this, then the next thing I would check is to be sure the thermocouple is connected properly to the safety valve. Unscrew it and check to be sure that the contacts are clean. Use a pencil eraser to clean any dirt off the thermocouple lead, then reinsert and tighten back down.

<font color="#FFFFFF" size="1">[ April 25, 2006 02:41 PM: Message edited by: lowracer ]</font>

[ha_asfan]

When I re-light my oven pilot, it requires me holding the red button in for 60 seconds. Any less and it doesn't want to stay lighted.

[lowracer]

Good point. Mine will often latch in at 45 seconds but you do have to time it. What feels like 60 seconds is usually only about 30. Watch the clock while holding in the button. Another thing you can do is use one of those long-snouted butane lighters to pre-heat the thermocouple before holding down the red button. This was a trick the appliance repair guy used when he came to check the oven.

<font color="#FFFFFF" size="1">[ April 25, 2006 03:09 PM: Message edited by: lowracer ]</font>

[stoveman]

Hi Lori, I would replace the thermocouple. As they age, they produce less and less current until the current they produce is not enough to hold the safety valve open. The magnet in the safety valve will also loose it's magnetism as time goes by. So you could have either or both giving you the problem. The thermocouple is the cheapest (5 or 10 bucks). If that doesn't solve it, get the safety valve rebuilt or replaced.

[Kitzig]

Mark, great picture, but mine doesn't look anything like that.

[img]http://static.flickr.com/17/94395944_c00b056254.jpg[/img]

Sammy, We did try replacing the thermocouple, and we tried heating it for a long time. It is getting gas to the pilot, but no where else in the oven. Then when we release the red button, out it goes. The thermocouple we puchased is different, but the gas gets to it. Is the next step replacing it, or can we even find one like this?

Lori G.

[stoveman]

Lori, I had forgotten that you have the Robertshaw "Mini-Pilot". The replacement for your mini-pilot is Robertshaw #1851-252. It is 24" and costs $88.64 at Patriot supply, but the 1851-253 is 36" and about 2 bucks cheaper. So now it is a new day. The cost of replacing the thermocouple has caused a change of plans. Now I would suggest using a Millivolt meter to test the old Mini-pilot. If you have one or can borrow one would be great. If not, Lowes/Home Depot/ Radio Shack has them for a reasonable price. I'm guessing that you should be geting about 20 millivolts when tested open citcuit. Somewhere I have more info on this and will try to post it shortly.

<font color="#FFFFFF" size="1">[ April 25, 2006 09:57 PM: Message edited by: The Uncertain Stoveman ]</font>

[stoveman]

OK, I found the info on testing thermocouples. It's a big picture, so will take some time to load.


[url="http://www.flickr.com/photos/74393054@N00/135133858/"][img]http://static.flickr.com/46/135133858_62811ac00d_b.jpg[/img][/url]

Just connect the millivolt meter to the end of the thermocou[ple and look for 12 millivolts or more.

[stoveman]

Here is the advised pilot flame. It should be adjusted to the smallest amount of yellow in the flame. Note: If the flame is too big, the mini-pilot will not produce as much voltage, so maybe your's needs to be turned down.


[url="http://www.flickr.com/photos/74393054@N00/135183115/"][img]http://static.flickr.com/54/135183115_dbbd0c60c5_o.jpg[/img][/url]

[Kitzig]

Sammy, Mark, ha_asfan, you guys are wonderful. I passed all the information along to my husband, so he is going to work on it today. I'll let you know what happens. Thanks again.

Lori G.