The maximum hot aisle temperature is not a fixed value, it depends of the equipment that you have running and your inlet temperature. Some equipment will run hotter (have a higher differential temperature) than others. As a general rule if your inlet temperature is within spec, the higher you can run your hot aisle temperature the better your facilities efficiency.
Unfortunately people that have to work in the hot aisle have a different opinion. I recommend you provide them with the appropriate clothing, like a Hawaiian shirt and shorts
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