Where do I place the logger?
Temperature in different parts of an area can vary significantly. Even in a small fridge, the temperature at the bottom could be a few degrees different from the top. In a big commercial cool room, the variation can be surprisingly large.
So where is the best place for the logger?
Well, it depends on your goal. If you want to get the average temperature in a fridge, for instance, you should generally place the logger in the middle of the middle shelf. If you want to measure extremes, move the logger around over a day or two to map the hottest and coldest parts, and then place the logger in whichever is most important to you.
Don't put the logger against metal surfaces
It can be tempting to put the logger against a fridge wall to keep it out of the way. Some people have even used double-sided tape to mount their loggers on a wall.
Unfortunately, this can significantly impact the logger’s communication. Radio waves don’t pass through metal. It is much better to have at least a few centimetres gap all around.
Tips: Legitimate ways to modify the results
"Buffering" the logger
If your logger is in an area that sees large and rapid changes in temperature – e.g. in a busy fridge in a warm room – it can be helpful to slow down the logger’s reaction to temperatures.
You can do this by placing the logger in a small cardboard box – like an old panadol box. In extreme cases, you might even place it in a small tupperware container.
Protecting the logger
Clever Loggers are not waterproof. If it is possible that they will be exposed to moisture – e.g. in an icy freezer – you should place them in a zip-lock bag or a plastic container to protect them. Note that placing it within a plastic container will significantly slow down the responsiveness of the logger (how quickly it responds to temperature changes).
Hot and cold spots
As a general rule of thumb, a fridge is warmer towards the top and towards the front. It will always be colder if it is the direct airflow (where applicable).
Over stocking a fridge will have a huge impact on hot and cold spots. Don’t over stock your fridge. Or don’t be surprised when you have a large variation from one location to the next.