While the small electric heaters are fine for keeping YOU warm, they do nothing for the underbelly water lines, tanks, ice maker lines, water pumps, etc...
Trust me, the water under there WILL freeze if the furnace (or some other heat source) is not on down there. A heated intake water hose helps that, but for other things, some have done 200 watt incandescent bulbs strategically placed down there - they DO out off heat.
Ours: '11 Monaco Diplomat 43DFT followed closely by '14 Jeep 4 dr Wrangler.
Hers: '13 Explorer Sport - AWD 365hp twin turbo scooter!
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