Sizzling noise when cleaning PC dust with canned air

zablablukas · 01 Jan 2017

I don't know if this post is appropriate for this forum section but hopefully it is. Today I cleaned my PC with canned air. Hadn't cleaned it for over a year. I opened it up, took outside and put it on a table. It wasn't too cold outside but not warm either. Then I started spraying canned air. Everything was going smoothly until I started spraying it on a part near the processor. I heard a sizzling noise. I do have to mention that I didn't give it enough time to cool off before doing this. After I was done I rigged everything back up, gave it a few minutes to go back to normal temperature and ran it. Everything does seem to be working smoothly. Though running it the first time was different. There was a different beep and I saw the "American Megathrends" screen (which I don't usually see). But running it the second and the third time was normal like always. The PC is more silent (as it should be after cleaning out the dust). Though I am still concerned about the noise. Could me being a little careless and not giving time for the PC to cool off have caused serious damage to the hardware? If you have any information about these kind of things please share it. Thank You in advance! :)

SoFine409 · 01 Jan 2017

You might be holding the can at an angle and some of the propellent is escaping in liquid form. When it does it is vaporizing and making that noise. Hold the can upright.

A5hm · 01 Jan 2017

When you cleaned the PC did you have it so the fans were not able to spin ? This I've heard can lead to a build up of static electricity.

Also did you keep the can upright when you were spraying ? Tilting it too far to a side or up side down causes the air to come out as a vapor and is very cold which i can imagine is not very good for the PC,

swarfega · 01 Jan 2017

I hope you cleaned your computer with the power off.

zablablukas · 01 Jan 2017

Yes I've cleaned it with the power off. As I said, I took it outside with me. Mos of the spraying was done when I was holding the canister directly above the fans. Though I did some spraying on the sides as well. The fans were able to spin when I was spraying. And yes I did tilt the can. Some rime appeared but not for long

swarfega · 01 Jan 2017

Thats fine then. Usually after using a air can you should leave the computer for about 10 minutes to allow the residue to dry completely.

zablablukas · 01 Jan 2017

Yup I did that. So I'm safe to say that I haven't accidentally fried anything?

swarfega · 01 Jan 2017

I wouldn't have thought so. I would just sit it out for a few days. If it still makes noises then consider taking it to a repair place for a check up.

zablablukas · 01 Jan 2017

Okay I'll keep track of the noises then

TV2 · 02 Jan 2017

Cleaning the inside of a PC should always be done with the machine OFF, power supply switched off, and power cord unplugged from the wall. You should wait about 30 minutes or more to allow all of the machines capacitors to drain power. This may seem unnecessary if you are using non-conductive methods to clean, but accidents do happen and this habit will help avoid any unpleasant surprises.

When you are cleaning a PC with compressed air, from a can particularly, it is good practice to give the PC 10 to 15 min to cool down before doing so. As SoFine49 stated, the gas in the can is in a semi-liquid form. As it escapes the can it depressurizes quickly and converts to a gaseous form. This depressurization produces a very cold gas (this is how air conditioning works), and some of that gas may still be in liquid form if there is a very short distance between nozzle and a hot surface.

The sizzling could be from liquid gas boiling off, but it could also be hot metal parts shrinking against each other as they cool down rapidly. Think of all the sounds a car engine makes when you first turn it off after a hard run.
The danger here is that the sudden change in temperature could crack hot parts. That is why it is best practice to let everything cool down first. I always blow my rigs out before I have turned them on for the day, after sitting off and cold all night.

The part about the fans: I was shown to stick a pencil (or other non-metallic stick) in between the fan blades to stop them from spinning as you blow them out with compressed gas. The reason I was told was that the fans can act as small electric generators (motors and generators work on the same principle in reverse) sending a charge back into the motherboard. This small charge will probably not cause any damage if the PC is OFF, but why risk it?