Transcool - exploding the myth
Firstly let's define air conditioning with a line from Wikipedia:
Air conditioning (often referred to as A/C, or air con) is the process of removing heat and moisture from the interior of an occupied space, to improve the comfort of occupants.
Transcool offer the leisure market evaporative coolers. These do not remove heat or moisture, so cannot be called air conditioning. But we will look at what they can provide.
To explain evaporative cooling we will go back to basics. Imagine a warm day and you are sitting outside in the sun. You dip your leg into a bucket of water and remove it. You will feel a chill over the wet area caused by the evaporation of water off your leg.
Oddly science tells us that the temperature of the water makes little difference with only a 3% increase in cooling when using water at 10°C compared with water at 32°C. Therefore the common practice of putting ice in the Transcool unit is just wasting energy and valuable fridge space!
On paper, with a capacity of 2 litres, the maximum cooling potential of the Transcool EC3 is 486btu/h (based on an eight hour period with the fan speed set on low).
The transcool unit increases humidity, okay if the humidity is low, but not so good for those who struggle more with high humidity than high air temperature. Note, if you decide to use the external 5-litre reservoir you will be adding 7 litres of water into your camper through evaporation, not something many would choose to do.
The CoolMyCamper cools at unit runs at 2400btu/h, reduces humidity and removes heat from your camper. If however, you want something that is better than nothing then consider a Transcool unit, but there are cheaper evaporative coolers around; just google "stand fan with humidifier".