Hello,
My situation is this: my rigs are in a closed rood with only two vents for AC coming in.
AC is stuck at 20C/68F.
The room is closed: no windows and no way for the air to get out.
The room also cannot be modified, since it's not my house and the owner has refused any modifications I proposed.
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Leave the door open?
The obvious solution would be to convert one of the two aircon inlets into an outlet. Might be very easy if you are handy, or a complete disaster if it goes wrong.
But as others wrote already, you need to let the heat out, somehow.
How about a few extra washers placed on the door hinges to lift it off the floor to create a leak?
What is above the room?
If you have a quality wood door.
you could remove ½ to maybe ¾ inches from bottom of the door.
Good luck fixing the heating issues.