Coleman Hot Water Service 12V Conversion, run it when the battery dead

The Coleman hot water service is an awesome piece of camping equipment, it allows you to have a shower anywhere when you are out camping.

However the only issue (that I have found) with the unit is the battery. More times that I can remember I've only got one shower out of the unit (as the battery died) or I have forgotten to charge the battery before heading out bush. Plus you can't run the unit when you are charging the battery.

So to solve my problem, I decided to make a power supply for the unit (as the unit runs of 6V) so I could run it off my car's 12V socket. I wanted the power supply to be integrated, as I didn't want switches to flick or extra cables coming out of the unit.

My power supply allows the unit to function like original with the extra bonus when the battery dies you just plug it in and the unit will keep on giving you hot water and charge the battery.

The power supply plugs into the original connectors inside and is attached to the case via stick on mounting posts.

I also incorporated a low voltage (12V side) shut-down so not to flatten your car battery and a detection circuit so you can't run the hot water service while you are charging the battery from the (240VAC) wall charger. (Also the wall charger can't handle the current.)

I was also toying with the idea of making some more of these if anyone is interested.

Below is pictures of the power supply installed into my hot water service: