The attached save has a cool steam vent with a inverse "U" of diamond temp-shift plates to cool the steam against the water already in there. However the temp-shift plates have widely disparate temperatures despite being right next to each other. The plates are in vacuum, but as far as I understand it, this should not matter. Note that the same plates work perfectly fine on the second cool steam vent (not in vacuum).
Load save, observe how the temp-shift plates at the cool steam vent close to the surface do not converge to the same temperature at all.