There is nothing in the listing that says the Power Supply has a temperature controlled fan. The control circuit is poorly implemented. The fan was defective upon receipt. To disable the temperature control solder a 32 ohm resistor in place of the thermistor wire, and the fan will run always with a slight undervolt at 10v. The thermistor is wrong resistance, so the fan barely turns on even when necessary. There was also a loose piece of wire stuck on the flux inside the PSU. These high voltage PSUs are very tricky to work, need to be very careful with large capacitors.