Interference occurs after replacing new AP R550 instead of R300

[kyawmyo90]

I have a wifi replacement AP R550 instead of R300 of the clinic with 4 floors. all the AP are connected to Smartzone 144 with version 6.1.1.0. After replacing the AP, the client are experiencing the wifi disconnected and request time out issues. the APs are mounted in the walkway, we can get good signal strength in the walkway, but can't get in the rooms. in the previous AP, it isn't happen like that.  These APs are mounted relatively close to each other within 20 meters.

I'm looking to mitigate interference as much as possible. I have set 2.4 GHz and 5 GHz to default channel width. I am using 1,3,6,8,11 for 2.4. and 5 is default setting. The ground, 1st, 2nd floors, are experiencing wifi issues disconnected and frequently drop the connection, maybe interference but the upper floor wifi connection is good.

Please kindly suggest to mitigate the interference. Thanks for any help!

[Squozen]

You should only be using channels 1, 6 and 11 for the 2.4Ghz radio for a start.

[dk1089]

Try the below steps to narrow down the issue:

First try to find out if disconnections are experienced on the 2.4 GHz band, 5 GHz band, or both on these APs.

Keeping the channels under Auto mode will use the non-overlapping channels for 2.4 GHz (1, 6, 11). 

Also, you can verify the ChannelFly-related configuration under zone (advanced settings), as it will automatically force APs to switch to better channels where there is less interference or congestion.