Embedded Tomcat Timeout After 30 Minutes

We are implementing an embedded tomcat server in an application. We are running on tomcat version 6.0.26 and it is run as a Windows Service. The service starts fine and runs fine, but after exactly 30 minutes, it stops. There is no error in any tomcat log nor is there an error event registered with the Windows system logs. There is an event that says the service entered the stopped state. There must be some setting that is timing this out, but I can't find it. This is not happening when tomcat is running as a batch. What am I doing wrong? Thanks.