nmea2000 pgn 130316 extended temperature

I'm trying to display the output from a nmea2000 temperature sender but it's not one on my library.

pv780 

2.8

This is the info I've been given by the supplier but I cant seem to get it working.

Signed

Bit position 24

Length 24

Gain 0.001

Offset -273.15

Min -8661.758

Max 8115.457

Units Deg C”

Can anyone help?