hello Shaun, i found one of those thermometers you use in your mouth when are ill. here are my findings:Degrees c
when i turn on the rainfall shower and keep the thermo dial central, it measures 34 degrees. when i turn the thermo dial up, i get 40.2d when the shower is left running for a minimum 3 minutes. however, when i tested the hand shower, it went off the scale, which confirms that the handheld is hotter than rainfall, but it could be by a degree, so it could be 41 or 42. hope this helps