Microplate reader... with ice box?!

As the schedule of our bMG microplate reader is a bit crowded, I'm trying to use another plate reader machine which is much older than the bMG one. This old machine is somewhat odd: it's connected to Mac computer, put into a "simple" incubater (heated by a lamp...). What the most awkward is that it needs an ice box to cool down, otherwise its motor would overheat... So, since the ice box is for machine, it should be a special or an order-made model, right? Well, not really. It's just a normal water bottle wrapped in towel. That's it. Very strange cooling system eh? This is said to be Peter's idea... :P