When you are camping in a van, it seems you can never have enough battery power in reserve.
Whether you have a house battery system or are running off a portable battery pack, a mechanical timer switch ($10) can limit the load from high draw devices.
For example, let’s say you want to run an electric heater. Maybe not the wisest use of limited battery capacity, but not impossible. With a timer switch you can set it to run 15 min on, 15 min off, doubling your runtime and giving the battery time to recover. A side benefit is narrower temperature swings, as the on/off action works as a “thermostat” of sorts. Normally, if the van never gets warm enough, a thermostatically controlled heater would just run constantly.
A timer can also turn your heater on before you wake up, shut off the TV when you fall asleep, or turn your fan off in the middle of the night so you don’t wake up cold. These timers have LOTS of uses and no RV should be without one!
In this video we show how effective this can be, using a small ceramic heater. I use this in my Odyssey camper and although it’s not going to keep you warm at 0 degrees, it DOES make a difference. The switch and the heater are linked at the bottom of this page.
You can find all of my technical and minivan camper conversion DIYs, linked here.