Noise Reduction Chinese Projector

I have bought a Chinese LCD projector from eBay, of course as many say, why do you buy crap like that? Eeuh well i like buying crap and try to make something out of it.. In this case it was a DBpower LED 86+ (wifi) . I believe it is produced under several names , has a native 1280*768 resolution. The device works amazingly well, with one big exception: when you switch on the device and the fans starts roaring the machine makes more noise than my vacuum cleaner. after searching the internet i cam on a french Forum where a guy named whitearrow38 had replaced the Fans with more silence ones. Since this forum is in french i will try to explain it englisch.

also some warnings before you start:

Important remark, the power supply in the device is not shielded, and is connected to 230 V ( in europe) . so do this modification only if you are familiar working with high voltage, and do not forget to disconnect the power cable before opening the case !.

Please remember that you will loose your warranty when opening the device, and alter the fans,

The inside of an LCD projector is very sensitive to dirt and dust, keep the lid closed when you are not working on it.

Step 1: Material Needed

For tools:

1. Philips screwdriver with a long shaft ( to open the case).

2. . A soldering iron ( if you want to do it neatly).

For material

1. . 2 silent fans 92 mm ( i have used Noctua Casefan NF-B9 Redux 1600 ).(total cost was a little less than 30 euro)

2. Solder.

3. Insulation tape.

Step 2: Opening the Case

1. Turn the projector upside down, and remove all screws from the bottom, remark there is also a screw under the QC PASS label next to the hight adjuster screw and the airfilter.

2. Put the projector back on his feet and remove carefully the top. be carefull with the connected cable attached to the keypad.

Step 3: Removing the Old Fans

There are 2 fans for blowing hot air to the outside of the projector, both are cooling a heat-sink that is connected with heat-pipes to the LED Lamp.

they are located besides the control board. ( see picture).

1. I found it easier to first remove the power supply, this is easy, just remove 3 plugs and pull the supply out, it is not screwed , it slides just out.

2. remove the 2 screws from the mainboard, and curt the tie-wrap above the fan

3. unscrew both fan casings. both cases are fixed with 2 screws, and are located at the bottom on both sides.

4. the fans can now slide out.

5. disconnect the fans from the mainboard

Step 4: Mount the New Fans

1. cut the connector from the old fan with a little remaining wire, and strip a little of the wire

2. cut the connector from the new fan, and also here strip a little of the wire

3. solder the old connector to the new fan :

a. in the case of a normal fan:black to black (gnd) and red to red (12v)

b. in the case of an PWM fan connect black to black (gnd) and red to yellow (12v)

4. wrap insulation tape aroungd the soldered wires.

further installation is the same as removing the fans but than in reversed order. withe following remarks:

a. both fanse have the airstream in the outside direction

b. i want to advise before closing the closure, only connect and put the lid on, and do a test run to check if the fans are running fine.

Step 5: Before and After Modification

Before the modification the noise was extreme, after the modification the is a clear improvement noticable, to be honest i still find it loud, but it is much better than it was. there is in the lamp mount also a vent , that maybe is something for the future to improve.

I have tried to capture it on video, you can hear a difference, the pitch is lower, and the volume is a bit lower. i find it for sure less irritating when I am watching a movie