In a sharepoint 2013 farm i found below error in uls logs and unable to delete Search Administration Web Service Application and search service application status is stopped
SearchServiceApplication::GetQueryHealthMonitoringSettings--Exception: System.NullReferenceException: Object reference not set to an instance of an object. at Microsoft.Office.Server.Search.Administration.IntegerSearchSetting.GetConfigParameter() at Microsoft.Office.Server.Search.Administration.SearchSetting.GetSetting(String name, List`1 searchSettings) at Microsoft.Office.Server.Search.Administration.SearchServiceApplication.GetQueryHealthMonitoringSettings(String component)