Thermo Cube Thermostatically Controlled Outlet

I use one in my house. There is an area the pipes will freeze when the temps get in the low 20's and the wind kicks up.

I use an incandescent 60 watt bulb plugged into the Thermocube. It's been working for a couple years.
Eventually, I'll insulate the area so it's not needed.

The Thermocube does a good job, I would not hesitate to use in in the RV or anywhere else you want freeze protection..