Temperature does not trigger the rule

Setup, Configuration and Use Scripts & Rules
7

Add .toString after state.

rule "Temper above 20°"

when
    Item Temper received update
then
    if (Temper.state.toString > 23) {
       pushover("Temper over 23°")
       }
else
    if (Temper.state.toString < 23) {
       pushover("Temper aboves 23°")
       }
end

Or check this post for other clues that might help.