Given a small refrigerator / freezer (dorm fridge), would there be any reason why immersing the freezer coil in water would reduce or eliminate the ability of the system to remove heat?
I took a dorm fridge and adjusted the position of the evaporator such that it could be immersed in a container of water. Before adding the container of water, I ran the refrigerator, and it was easy to detect that it was removing heat (the evaporator coil got "frost" on it). Then I immersed the coil in a large volume of water, and ran the refrigerator again, but the temperature of the water did not decrease.
One possible reason is that when getting the container of water positioned, a crack developed, allowing the coolant to evaporate out of the system. But I was very careful, so wondered if there was another explanation, based on the physics, and the control system in the refrigerator.
An experiment could be done to remove the water and see if the coils frost again, but removing the large amount of water is logistically difficult, so I thought I'd ask before doing that.