Initially it didn't work for various reasons. You had space in field name so must be enclosed [in brackets]. When you did that, you made 32 a string ( "32" ) so also not good. Now that you have TempF you don't need brackets around it. That's the whole point of not using spaces or special characters in object names (save for perhaps underscore, which I don't usually use) and not starting an object name with a number.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.