I installed one of
These in our Jayco Freedom and thought I would post a pic. I think they are an awesome product and I can't see why they wouldn't work in a CT as well, as long as you have a 4000+ watt inverter. They are rated at 3000 watts but it takes less than 10 seconds for the water to run hot, so current draw on battery is only for short periods. They come in various configurations like
This and
This that could suit different needs and available space. Free post from Hong Kong took 10 days to arrive. Very easy to install.
If you would rather buy from a dealer in Australia have a look
HereBut if you look
HereI am tipping they are the same product. I installed a small ally bracket to the top of the spout with a hose clamp to keep it stable as it just seemed to wobble around a bit.