Battery Question

ticki2 wrote:

pianotuna wrote:


Take it out of storage at -37 and let me know how that works for you.

I sure would like to know your routine after you take your camper out of storage at -37 to warm the interior up to a reasonable temperature , with what heat source , and how long it takes .

Thanks for the question.

I have a decent size battery bank. The solar system maintains and charges the house, generator, and starter batteries. The charging is temperature controlled. This means the batteries are fully charged and kept at float.

Here is a step by step.

1. put magnetic heater on the bottom of the Yamaha generator.
2. turn on inverter to power the heater
3. wait 30 minutes
4. start the generator (sio2 equipped)
5. start electric heaters and plug in block heater for engine to the limits of the generator--which is also recharging the teleco batteries.
6. start furnace
7. furnace runs constantly for about 2 hours, as do the electric heaters.
8. start engine.

The various electric heat sources consist of heated electric carpets, oil filled heaters, 1 radiant heater (good for thawing compartment doors and the like), 2 fan based heaters. I protect the fridge with a 60 watt light bulb controlled by a themocube. I have fans in the fridge chimney and they restrict air flow somewhat in the winter time.

In the -30ties I'm able to heat 100% electrically, if there is sufficient shore power. The furnace set to cycle on should the power fail. The power needed is 4300 watts (continuous) with a peak load of 7100 watts. Total consumption for 24 hours is about 129 KWH.

To do this on a thirty amp RV I've added two auxiliary shore power cords, (15 amp and 20 amp). I have a "break out box" for 50 amp that has a 30 amp outlet on one leg and twin 20 amp outlets on the other leg. Each outlet has its own breaker.

Because power drops by the square of the voltage, I use an autoformer on the 30 amp service to provide sufficient voltage to keep the electric heaters working at peak output.

I have a hybrid inverter/charger which I operate in load support mode. I do limit the amperage on a 15 amp shore power to 13. On 30 amp the limit is 24 amps--or just about the same output as the Yamaha generator.

I've done some "back yard" experiments that document heating time and energy use both before and after modifications I've made. They exist somewhere on the boards. Try the winter camping thread on the full time forum?

I'd be delighted to answer any questions you or anyone else has.