Conflicting information in the link. My best guess is 2010 Month 11.The only way to be sure is to phone them.EDIT to Add./ I just noticed you typed 'Whirpool', I have edited your post but am not able to edit my link. When it opens, add the 'L' and press Enter.https://www.google.com/search?q=How+old+is+Whirpool+Gas+Range..
I am a retired career chef, and had this one oven with choking CO in an airport catering kitchen. We had it serviced and it was fixed. It sounds like yours is not getting enough air mixed with the gas. Adjusting the gas is one thing but the venturi to the burners can partially block and unburned gas spills over. Remove the burner and venturi and boil it out in whatever you boil your fryers out with.
Are you on mains gas or propane because the jets are different.
https://www.google.com/search?q=commercial+oven+emitting+too+much+Carbon+Monoxide
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