I have trouble comprehending exactly what you're doing each time, but it appears that in that test you had no problem measuring a water temperature increase. Is that correct? If the water is cooling quickly it is likely not well mixed. Have you left the water underneath the pan for several minutes (0+)? -Scott Reply gbaikie says:  July 0, 0000 at 0:00 PM  -I have trouble comprehending exactly what you're doing each time, but it appears that in that test you had no problem measuring a water temperature increase. Is that correct? 