Khun Siranee,
Thank you for your quick support.
I believe so, any mistake should not happen by manufacturing unless.
I was not involve during commissioning, so I have no idea what was happened during that moment.
But since I was here until now, there was no any work to replace the pump impeller for sure.
I believe that there was not spare impeller stored, so if the pump had been replaced the impeller in the time in between you should get the order of impeller like I did recently.
Should you or manufacturing tracking that had any impeller ordered during the commissioning till my order, to ensure that the impeller was replaced not a mistaken?
In the order hand, I would check with my colleague who involve during commissioning for more clear then.