VanDweller Community Forums

Full Version: Adjustable speed low amp computer 12v fan
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
I am a bit of a ventilation Nazi.  I've got computer fans everywhere.  2 counter rotating fans inline on the ceiling for exhausting, 3 fans in a side window for intake. 2 fans on goose necks on a 2 inch spring clamps positionable anywhere within,  for internal air movement, One on my fridge, one exhausting the fridge/electronics cabinet. And, just to prove I am a ventilation Nazi, I ran 8 AWG cable to my new Hvac blower motor, and the thing now moves more air on medium high speed than it did on high speed before. 

I've found the most convenient computer fans are the ones with built in speed controllers.

Not many Fans have this function built in.

The Silverstone fm121 has been a favorite of mine for many years now.  Upto 110CFM at 0.4 amps and down to 33CFM at 0.08a 
A newer acquisition, has been the Silverstone AP182 which also has a speed controller and can move some serious Air at full speed and is practically silent on its slowest speed.

I use this as an intake fan in front of my conversion van sliding window.  I put 3 fans on a shroud for positive air displacement, and it is rare that it is so hot, that i need to turn on all 3 fans.  The AP182 pretty much runs 24/7 even when cool out.  It draws only 0.05a on the slowest speed.

When i have my windows blocked off, and the fans on, my interior is almost never hotter than outside, late afternoon being the exception.

I just saw Silverstone came out with a new slimmer design 180MM fan with adjustable speed control, and it is a reasonable price on Amazon of 16$.

I would certainly have bought this fan instead of the AP182,  as it claims a marginally higher CFM at max speed as well as having a lower amp draw at max speed by over 50%.  171 CFM for 0.54 amps is impressive!

The AP 182 I employ, was 26$ and draws significantly more amperage at high speed( 1.3a).  Its hub also gets way too hot at high speed at battery charging voltages.  I use a voltage limiter to keep voltages under 12 to the fan, which does limit maximum speed( and amp consumption).

The Ap 182's steering vanes make the airflow out straight in front of the fan in a dense column of air.  It appears the fans without these steering vanes move air outward at steeper wider angles.  So the Ap 182 can be used and Aimed internally more effectively, but if just exhausting Air or used as an intake the FM182 takes half the electricity to move as much air, and is just 0.04amps at its slowest speed.

Anyway, it is that time of year, and both high CFm ratings and low electrical consumption ratings and adjustable speed built into the fan controller, make these fans winners.

If one wants to incorporate speed control into computer fans they already employ:

If the hub of the FM182 gets too hot at high speed,  and voltage limiting is required, I use this one which has a voltage display:

But I also own smaller less expensive versions without the voltage display.  One needs a separate voltmeter to set the desired output voltage:

These can also be used as speed controllers, but one has to bust out a tiny jeweler's screwdriver to adjust speed, rather than grab a Knob and turn it.  

Stay cool, Dwellers.
Thanks for the info.
We will be in the PNW for a while this summer and I was looking into a couple more fans to keep air moving to ward off mold, especially in the under bed storage.
I had wondered about using a voltage limiter to keep from cooking fans while charging.
I'm sure glad I did the solar upgrade before this trip. Our old system just wouldn't have kept up with our basic usage.
I used these in AV workstations I used to build:
How well would the Silverstone fm182 work against the wind? Sometimes the shifting wind can be a challenge for a fan. As long as it wouldn't burn up, that would be fine with me.
I leave my AP182 on when driving as an intake fan. It is in a rear conversion van sliding window. Basically the airflow INWARD through this window increases when driving and would cause the fan to spin faster.

The Impeller on the AP182 is quite heavy so it is likely less affected by wind than the FM 182, but I am making an assumption that the FM182's impeller is lighter from the much lower Amp draw at full speed.

I did have the speed control electronic chip fail on one FM121 long ago. This was on my ceiling and I drove on the highway with the mushroom vent removed, and the Airflow likely caused it to spin much faster and fried the controller and it only worked at full speed thereafter.

I can sometimes hear my intake fans fighting the wind when not moving. It does not seem to bother them, they just seem to speed up and move less air when they are fighting the pressure.