fan ramps but never drops

[Wing-Man]

Evening all, the Fan on my PSU Ramps when underload, and some times when not under load.
But ever way ones the Psu Fan ramps it never go's back down until i power cycle the system.

is there a fault? is it someing i can RMA for, and dose it need to be RAM'ed(could it be a fault that becomes a bigger broblem)

PSU - https://www.overclockers.co.uk/lian-li-sp750-sfx-modular-80-plus-gold-power-supply-ca-79g-ll.html
I got it from OcUK

 

[Wing-Man]

But in there cool testing at 25c the psu is fine, my room is around 22c and my case O11 mini as the psu in a separate part of the case so the cpu/gpu shouldn’t be affecting it too much.

I removed the filter that’s next to the psu f or better air flow. I will see how I get on

let not forget when the psu run away it was tested in a room at 45c but the temp went up to 47c and the psu was run at max watts/amps. My problem is in a room at 22c ish and idle power draw