Webasto furnace shutoff?

[Islander220]

I keep my R29 in a boathouse over the winter, and I don’t want the Webasto furnace to come on. The lowest that i can set the webasto control is 42°F. Ihave pulled the fuse, but the screen still lights up?
The boat has a heater, which will come on automatically if the temperature falls to freezing.
Is there some other breaker that I’m missing?
I would appreciate any advice
Thanks!

 

[Submariner]

I keep my R29 in a boathouse over the winter, and I don’t want the Webasto furnace to come on. The lowest that i can set the webasto control is 42°F. Ihave pulled the fuse, but the screen still lights up?
The boat has a heater, which will come on automatically if the temperature falls to freezing.
Is there some other breaker that I’m missing?
I would appreciate any advice
Thanks!

There are 3 fuses for the Webasto heater. Thermostat, fuel pump and the heater itself. They are each a different size fuse also.
I just turn mine off using the thermostat. It has an on/off setting that ignores the temp.