Hello @Customer4173,
thank you for your interest in our hosting.
Application pool timeout works when no requests have been made to website in last 30 minutes. This means that no user has visited your website during this time than server puts your website to sleep. If your website has visitors server keeps it running all the time. This setting saves resources on server. When new request to your website is made after 30 minutes, server will wake up website and your application will start again.
What specific problem do you have with this setting? This timeout limit cannot be increased in Free plan.