I've created a small liquid cooler and would like to test for it's cooling capacity. The only way I know of doing it is to circulate the coolant into a small reservoir with a heating element and apply power adding heat till the cooling unit is maxed out holding at a predetermined temperature. Then calculating the wattage by volts * amps. The test equipment would be well insulated to minimize transient heat. Is there a better way or off the shelf apparatus to do this?