BrewBrain have many users that have very good reception with the Float inside a stainless steel fermenter, which is placed in a fridge.
Since everyone's setup and wifi strength differs substantially, we cannot guarantee that you will have good reception with a similar setup.
Our advice is to place the WiFi router as close to the fermenter as possible to ensure good reception. If this is not possible, consider using a WiFi repeater, set it right outside the fermenter.