Losing Our Cool

One of the problems we came across during our trip was the current draw of our chest freezer and the upright fridge in hot weather. We were finding that we were drawing more power than we ever had before. A temporary solution was to cryovac all our meat then freeze it in the chest freezer along with a bag of ice. It worked well enough but it showed that something wasn’t right because we had never run out of power overnight before.

When we got home I ran a few experiments to see if I could track down the problem. I was able to use a temperature logger to see how the freezer was working and compared it to the ambient temperature. It was from that experiment that I discovered that the freezer was not turning off when it reached the correct temperature. We decided to bite the bullet and buy a replacement freezer as the old one was seven years old. When the new freezer arrived we were able to run it on one of the auxiliary batteries for three days without flattening the battery completely. Similarly the fridge ran for a couple of days without problems on just one battery.  We had struck a problem earlier in the trip when our solar panels weren’t charging properly because of a dirty connection. Once that was cleaned the system then worked properly again. With this in mind we purchased a blanket type solar panel that will allow us to add extra charging to the system when we pull in of a night. I also added some computer fans that turn on when the compressor of the fridge or freezer is running so that we get better air movement over the compressors and the cooling coils. I also ran new 240V wiring so that when we are plugged into mains power the fridge and freezer run directly off the mains power and allows our batteries to fully charge while connected to the power.

I’ll wait till after Christmas to experiment on  how the system now works off grid in hot weather.

Daytime Running Lights

We installed additional LED Daytime Running Lights as we found the existing lights were ineffectual on dusty roads in bright sunlight. We were turning on the headlights to make ourselves more visible but found that it would automatically dim all the dash lights and the sound system screen, meaning we couldn’t use the handsfree system to make calls. The new lights are switched on manually via an illuminated toggle switch located next to the Hot Water Exchanger switch. The LEDs are extremely bright and compliment the existing daytime running lights.

The new LED Running Lights mounted on the bullbar adjacent to the existing running lights
The illuminated lights switch for the new running lights

The Updated Hot Water Generation System

The new heat exchanger system

We finally completed the updated hot water generation system. This involved installing a heat exchanger under the bonnet connected to the vehicles cooling system that then heated water being circulated through the heat exchanger from the onboard hot water service. This meant plumbing in two solar hot water service pumps that are capable of running at high temperature (with built in systems to prevent overheating), a temperature sensor that gave us the ability to turn off the pumps when the hot water reached 65°C and a dash mounted switch and indicator lights to operate the system while driving. The end result is a system that generates hot water using the heat of the engine and provides us with “free” hot water in under 30 minutes of travel time. This will allow us to heat our hot water before we reach camp each night and the insulated hot water tank means we have hot water for hours after stopping.