Just got off the roof, where I measured my installation with an IR thermometer. Believe that's what Bob meant by heat gun.

Exposed roof: 135 to 140F, 57 to 60C
Shaded roof: 100F, 38C.
PV panels: 120F, 49C

Jim


On Wednesday, June 28, 2017 at 8:56:15 AM UTC-7, Dan Marotta wrote:
How did the temperature of the roof surrounding the PV panels compare?
Dan, 5J