Quote from: Xian01 on November 14, 2014, 12:30:45 PM

I'm interested in tinkering with turning a couple S3's into space heaters now that it's getting colder.

The aim would get to get two of them quiet enough to run in a bedroom or office.

Could someone experienced offer any insight if stacking a few non PWM low speed fans in sequence, on each end of the miner, work to push enough air through the unit more quietly ? Any recommendations for fans to that end ?

Not sure about going for non PWM fans - surely they'll just run flat out and be even more noisy?
On my S3s, I use a Corsair PWM SP120 High Performance 120mm on the inlet and a Thermalright PWM TY143 140mm on the outlet (screw holes fit 120mm spacing).
This makes the S3s much quieter than with the standard fans. Temps are up by 1 or 2 degrees (those standard fans are powerful things) but it's an acceptable trade-off.
Mine are in my office and this has been well worthwhile for me. Not sure if I would want them in my bedroom though - any fan will sound mighty loud in the wee small hours!

You could always try doing just the one S3 to start with, to see if it gives the level of noise reduction that you want.