Dickinson P9000 Operating And Installation Instruction page 16

16
Electrical 12v Fan
The fan inside the heater is 12V DC .17 amps and the power supply must be
brought to the wire connectors of the fans ON/OFF switch through the
grommet installed at the bottom of the heater. The fan installed in this
heater is CE approved and EM compliant for FCC and CSA regulations. The
fan must have an inline fuse rated at 2 amps.
If applicable, this appliance must be electrically grounded in accordance
with local codes or in absence of local codes, with the National Electrical
Code, ANSI/NFPA 70, or the Canadian Electrical Code, CSA C22.21.
NOTE: Red wire goes to the positive side of the battery and the black (or
possibly blue) wire goes to the negative side.