Question about Astron SS-30.

[N4KVE]

I have several of these supplies. I have done the resistor mod to allow the fan to always blow, but at a slower speed, vs the fan come on, & off, making lot's of noise when it's on. My question is, does the fan suck air into the back of the supply, & blow it out the vents in the case, or does the fan suck air out the back of the supply, sucking it in through the vents in the case. I feel air blowing out the back of the fan, & the vents, so I don't know which way the air is flowing. Due to the location of the supply, it would take a long time to "dig it out" to open it, & verify, so I'm wondering if anybody knows. Thanks.

 

[prcguy]

Mine blows air into the box. Don't know why they do that as pulling air into the box and out the back is generally more efficient.
prcguy

I have several of these supplies. I have done the resistor mod to allow the fan to always blow, but at a slower speed, vs the fan come on, & off, making lot's of noise when it's on. My question is, does the fan suck air into the back of the supply, & blow it out the vents in the case, or does the fan suck air out the back of the supply, sucking it in through the vents in the case. I feel air blowing out the back of the fan, & the vents, so I don't know which way the air is flowing. Due to the location of the supply, it would take a long time to "dig it out" to open it, & verify, so I'm wondering if anybody knows. Thanks.