it is always better to extract heat.
Because heat exchangers, pipes and other vessels run hot, forcing a cold environment on them can create stress cracks and other fatigue. Extracting the heat will introduce new air in from other areas (eg through the internal vents above the fridge) and it won't be as cold. This makes a gradual but even heat loss, with less sudden impact.
Secondly, because extracting will cool it down gradually and more evenly, the thermostat for the new fan won't be flicking on and off as frequently, which would reduce its life also.
And lastly, it requires less energy to remove heat, rather than keep it in place, and try to actively cool it instead.
