Jan 21, 2019 - 01:30 AM
Thank you for contacting Biobidet Support.
The USPA-6800 does have a deodorizer fan you are hearing everytime you sit on it. This feature "can" be disabled if you shall choose and this "could" explain why you may not hear it now.
If you have the base model USPA6800 this function cannot be turned off or on by default.
IF you have the USPA6800U (Ultimate version) you can press the Fan button located on the back of the remote that looks like the air coming out of the vent shown on page 9 of the Owners Manual.
If you should need further support, please contact us at email@example.com
Source: USPA6800 Deodorizer Fan