You are carefuly cleaning your computer graphics card or mechanical keyboard. Feeling like a pro using that can of compressed air. Suddenly, there’s water on your pins.
A fan is spinning too quick. What happened? Turns out you’ve been treating the thing like a magic wand.
Safe PSI For Cleaning Electronics With Compressed Air
How Compressed Air Dusters Work
In fact, it’s a real-world machine with physical limitations. It’s not that the air is bad, though. It’s that the air gets cooler and it’s delivered under pressure.
Inside the can is either difluoroethane or tetrafluoroethane. Both of these compound are refrigerants with very low boiling points. Under pressure inside the can they is gas.
When the pressure are released, the gas expands quick. That rapid expansion make the air really cold. How?
This happens because of something called Joule-Thomson effect. If you don’t understand what happen, just know: your tool will be a frost generator. There is no single magic PSI number for safe range.
It’s more about knowing where pressure and sensitive parts intersect. I would say most dusters works in the 30-80 PSI range. Applying concentrated force by pushing material into small areas become dangerous.
The Danger of Upside-Down Spraying
Also it creates condensation which can short circuit. So how do you manage that force to protect your gear? Knowing what is in that refrigerant mixture make a difference as to how you grip the can.
If you grip the can upside down, then you are spraying liquid. As soon as this hits the cooler part/component, it will start boiling. The instant result is frost.
When that frost hit your motherboard, it melts into water. Electricity + water = no good. Therefore, the can must be kept upright at all times.
That way, only gas come out. The gas create airflow but does not cool quickly. Just this little tweak will save you some repair bucks.
Optimal Distance and Burst Technique
It’s about distance. If you’re holding the canister nozzle six inches out, the spray spreads fast. That is how far the spray travels before it lose its momentum.
It becomes nothing but a soft gust of gas when it reach the object. That’ll be fine for something stationary such as a dust filter. But for a concentrated heat sink, you want a focused stream.
Get right up on those narrow fin and blow ‘em clean. Getting close will also make your impact speed higher. So, you gotta figure out penetration vs reach.
Two to three inches out should of do for narrow areas. This is enough to blow off the dust without pushing it further inside the silicon. Only use it in burst mode.
Don’t spray for too long, as that will just overheat the can and waste product. Besides, the longer you spray, the more likely there’s going to be some moisture collect in there. With long bursts, the can cools off fast.
That cool metal cause the water vapor in the air to condense on outside of the can. Then that moisture drips on your work. Half-second short burst not only clean out the area but they allows the can to heat back up.
This keeps the pressure constant and keep frost from forming. You get into a rhythm pretty fast. Spray for a second; wait for two seconds.
Choosing the Right Duster Brand
So there’s a difference between these things, but it’s pretty minor. It’s mostly brand. They use different blends of propellants.
Some contain oil to help with lubrication. This sucks for an optical sensor. It is OK for a mechanical keyboard.
Some are straight-up hydrocarbons. Read the box. Avoid oil?
Check the box for oil content. Check the box for oil. Fancy GPU/lenses?
Get the stuff that isn’t full of oil. The thing about the brands is they all has roughly the same pressure rating. They vary a little bit by the type of chemical used and the nozzle shape.
A wider nozzle mean less peak PSI. A narrower straw-thingy means more bang. So pick your tool head accordingly.
Controlling Humidity and Frost
Control your environment. That’s how you protect your investment. Clean in a dry room.
Condensation happens when humidity gets too high. Cold gas sucks moisture from air. Moisture forms on your warm electronics.
First wipe down your work space. Have a microfiber cloth handy. If you notice white frost, stop and let it warm to normal.
No heat guns! Thermal shock is far worse than dust. Last, be patient.
Don’t use the wrong pressure, or you might create new issues while trying to clean correctly.
