G'day Thomas,

No, you wouldn't be able to use this adaptor as the AquaHeat requires a 5A initial draw while the adaptor is suited to low draw at 3A. There is the Companion AquaHeat & AeroHeat AC Power Adaptor which is best to use if you wanted a 240V adaptor to use/charge your Companion AquaHeat.

G'day Diane,

No, it won't.  12v Lead Acid batteries actually require 13-14.5v to actually charge.
This transformer steps down 240v and produces a constant 12 volts to run 12v appliances.
Whilst this with suitable to run 12v light off of, charging 12v batteries has different requirements to running appliances.

G'day Maree,

Yes it can, this is designed for use with any low draw 12v appliance that draws 3A or less.

G'day David,

Unfortunately not, the 12V kettle will draw 200W, so quite a bit more than the transformer can power. Best bet will be to stick to using your 12V kettle from a 12V outlet in your vehicle.

G'day Christo,

The simple answer is no this won't work to run a 12v fridge. The maximum draw that the Transformer can handle is 3 Amps. Most fridges will draw significantly more than 3A on initial start up even if the overall draw is 1 - 1.5A.