Webasto Airtop 2000 Power Consumption

[Ephesian]

I'm rewiring the boat, and have now got the heater - a Webasto 2000 airtop. Just looking to size the new cables correctly. Manual says it draws 9-22W, so at 12V I'm figuring 2 amps to be sure. Cable run is maybe 6 metres out and back. So I figure I'll be fine with 18 AWG.

However, the old cable I ripped out is way thicker, maybe 12 or 10.

Am I missing something? I wouldn't have thought a diesel heater would draw much, just enough for the fan and to get the glow plug going.

What do you reckon?

 

[the_branflake]

What size fuse does it say to use? My Eber has a 20amp fuse in the loom, it can use upto 100watts at startup then it reduces power down to 8-34 watts i think it is depending on the heat output required.

 

[Ephesian]

Ah. Manual says 15amp at 12V. So probably does need AWG 10 then...