Change fan to another fan connector

[andreast]

Hi , all.

Our server Proliant ML350e Gen8 v2,  had problem with noisy fan. We use 2 Fan. Tried with upgrade ILO firmware, but not successfull. Fan1 that connected to fan connector 1 is really noisy , tried to move to fan1 to fan connector 3 and fan1 operate normally. But cause error 1611 - CPU Fan Failure when booting, but I'm sure that fan operated normally , it spin. 
My question why I can't move fan1 to connected to fan connector 3, and cause the server shutdown.

[Cali]

The Servers have a special designed Airflow inside.

To reach the needed Airflow design, the propper installed Fan positions are checked.

I would recommend to buy the additional two Fans, they are cheap.

This give you redundancy and lower the Fan Speeds.