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Optoma HD70 shutting down. Neep help.

post #1 of 25
Thread Starter 
Well finally after three wonderful years of operation my HD70 its dying... I have tired two different bulbs and the problem persists. I can watch tv for a about 10 mins then it beeps at me the screen goes black and the red light indicating the bulb is having an issue comes on. I am assuming that light means the bulb is over heating. It shouldn't be having a temperature issue considering I have used it for long periods of time in the summer went it was really hot. Any one know what could be causing this to happen? Thanks

Austin
post #2 of 25
Maybe a fan has failed..... is it quieter than usual? is there plenty of air from the exhaust?

On most projectors the pattern of flashing usually indicates what the fault is. Have a look under troubleshooting in the manual and it should tell you what your particular pattern of flashes might mean.
post #3 of 25
Have you opened it up and blown all the dust out? If you are past warranty, this might be agood first attempt to solve this. Seems to be supporting evidence here on the forum from what I've read recently.
post #4 of 25
Thread Starter 
Yeah I took a few panels off and cleaned most of the accumulated dust out. It could be the fan. It doesn't sound any different but maybe. I'll check the manual. Thanks
post #5 of 25
Quote:
Originally Posted by Holmquist View Post

Yeah I took a few panels off and cleaned most of the accumulated dust out. It could be the fan. It doesn't sound any different but maybe. I'll check the manual. Thanks

The thread I was reading said you have to open the whole unit and clean dust off everything including the color wheel.
post #6 of 25
Thread Starter 
Hmm well I have tried using it a few times and it works great for 15 mins or so then the picture starts changing color and it shuts down with the same bulb error light. Two different bulbs it does the same thing. I guess I'll try completely disassembeling the unit and cleaning all the dust out.

Austin
post #7 of 25
Bulb changing colour could indicate a PSU/ballast issue...
post #8 of 25
While you are inside, have a look for burnt components or bulging capacitors.
post #9 of 25
Bulbs don't change color. Any color issues is going to be the color wheel, or it's controller or the image processor.
post #10 of 25
Not true. They colourshift as they age (towards blue) and colour can be changed by increasing the current (becomes more yellow) or decreasing the current (becomes more blue).

This is not the preferred way of doing things though - but it can easily be demonstrated with a variable power ballast, there were some jap imports where you could adjust the colour temperature of the HID lights by adjusting the ballast - starving the bulbs would get you bluer light (and lower output) whereas overcurrent would get you yellow (and higher output).
post #11 of 25
Quote:
Originally Posted by heathyoung View Post

Not true. They colourshift as they age (towards blue) and colour can be changed by increasing the current (becomes more yellow) or decreasing the current (becomes more blue).

This is not the preferred way of doing things though - but it can easily be demonstrated with a variable power ballast, there were some jap imports where you could adjust the colour temperature of the HID lights by adjusting the ballast - starving the bulbs would get you bluer light (and lower output) whereas overcurrent would get you yellow (and higher output).

Uh, if you read the thread you would understand the color shift is large and rapid, not a gradual shift over the life of the lamp and not due to voltage fluctuations.

When the color wheel on these dlps gets a heavy enough dust layer on them they throw the speed off enough to lose synchronization with the image circuitry resulting in weird colors before it shuts it down because of the sync problem.

Could it be electronic? Sure. However, it's more likely a dying color wheel or one with too much dust on it.
post #12 of 25
Thread Starter 
I have it apart now and in front of me. There doesn't seem to be any obvious damage. Just lots of dust. Taking things apart and putting them back together is no issue for me but diagnosing this thing is definitely out my range of skills. So I will continue to look around and clean it. But I will describe the issue again just so we are all clear. It turns on fine and lights up just like it should. It sounds normal, fan one is working properly. After 15 20 minutes it makes a strange beep sound "sometimes it changes colors green, blue, red. This does not happen each time." then the screen goes black and it locks down with the bulb error light illuminated. If I unplug it, let it sit for a minute and turn it back on it will repeat the 15-20 min view time then yada yada. I have tied to different bulbs and the same happens with each. Bulb one has 2100 hrs and bulb two has 1600 hrs. Please what the heck is happening to me! Thanks for all the help.

Austin
post #13 of 25
Bulb one has 2100 hrs and bulb two has 1600 hrs.

Bulb two went bad earlier, you need a new bulb.
post #14 of 25
You said that the projector makes a strange beep sound and changes color. Does the beep sound like it comes from a speaker, or is more like something mechanical inside is sort of buzzing or vibrating? It might be almost like a cell phone in vibrate mode only at a higher frequency. Also, do the colors flash in a somewhat controlled manner where they look almost like some sort of test sequence, or are you actually getting a more random flickering and color shifting in the image before it shuts down?

If the buzz is not from a speaker, and the color change is more like flickering and color shifting it could be the color wheel position sensor is losing sync. If this happens the control loop for the color wheel may go a bit crazy trying to adjust the speed of the color wheel to an input that is wrong. This out of sync drive to the motor can actually make the motor itself buzz. And of course the projector will have no idea where the color wheel actually is at any point so the colors will shift and flash. If the color wheel does not spin it can overheat and crack, so the projector will have a watchdog timer looking at the control loop to make sure it stays in sync. If the wheel does not get back in sync fast enough the projector will shut down to protect itself from damage. The wheel can over heat and crack in seconds so the timer will be set to a short amount of time, and the whole flash, buzz, shutdown sequence will probably happen rather quickly unless the wheel recovers a few times first before losing sync entirely.

If you do have a problem like this, there are several things that might have caused it. If you are lucky, some dust or dirt got onto the color wheel near the mark used by the sensor. If so some normal cleaning may fix the problem. But it could also be the sensor is failing. That is not unheard of since it sits so close to some very hot components. It could also be that the bearings or motor driving the color wheel have worn to the point where they are starting to bind and the motor is unable to keep the wheel in sync. Unfortunately these later two problems are well beyond any typical customer repair. And be aware that the ballast on these projectors produce a very deadly high current output. Do not even think about doing any repairs yourself unless you know the risks this involves.
post #15 of 25
Thread Starter 
Well knock on wood but it has been on and running just fine for an hour and a half now. I cleaned it very thoroughly and paid a bit of attention to the color wheel which did have a fair amount of debris on it. And fan #2 was really dirty. Anyway I think I got it working properly now. Thanks for all your help.

Austin
post #16 of 25
Quote:
Originally Posted by guitarman View Post

Bulb one has 2100 hrs and bulb two has 1600 hrs.

Bulb two went bad earlier, you need a new bulb.

This was a likely option since there is a lot of variability in lamp life, and it may still turn out that the OP's problem returns soon because the lamp is starting to go. However when there are other symptoms such as the color shifting and buzzing it can be a good idea to consider other failure modes before replacing the lamp. I have seen people spend money on new lamps only to find that the same over heating or sync issues occur with the new lamp. Unfortunately the typical user is not going to have access to a known good lamp or other spare parts to help in debugging a problem like this. In fact, a repair center is just as likely to miss something like this, replace the lamp, test it for a few minutes, and then ship the unit back with the same problem.

A projector is a very complex little device with a seriously nasty internal environment. Add to that the fact that this part of the forum deals with the lower end cost-reduced products and all sorts of strange failure modes are possible. I for one find it amazing that these things work as reliably as they do with many people getting years of trouble free use.
post #17 of 25
Quote:
Originally Posted by Holmquist View Post

Well knock on wood but it has been on and running just fine for an hour and a half now. I cleaned it very thoroughly and paid a bit of attention to the color wheel which did have a fair amount of debris on it. And fan #2 was really dirty. Anyway I think I got it working properly now. Thanks for all your help.

Austin

Glad to hear it! Too dusty is validated again!
post #18 of 25
Set the unit to High Altitude in the menu. It worked for me.
post #19 of 25
You're talking about a GRADUAL OVERALL SLIGHT shift in color, not the dramatic shifts and strange uneven colorations and anomalies reported in these forums.

The problems reported frequently here and in other forums will NEVER be the cause of the lamp. Lamps just do not behave that way.


Quote:
Originally Posted by heathyoung View Post

Not true. They colourshift as they age (towards blue) and colour can be changed by increasing the current (becomes more yellow) or decreasing the current (becomes more blue).

This is not the preferred way of doing things though - but it can easily be demonstrated with a variable power ballast, there were some jap imports where you could adjust the colour temperature of the HID lights by adjusting the ballast - starving the bulbs would get you bluer light (and lower output) whereas overcurrent would get you yellow (and higher output).
post #20 of 25
Thread Starter 
Days later it is still working excellently with the original bulb which has about 2175hrs on it. I think the issue was the CW being obstructed by excessive dust.

Austin
post #21 of 25
Quote:
Originally Posted by Holmquist View Post

Days later it is still working excellently with the original bulb which has about 2175hrs on it. I think the issue was the CW being obstructed by excessive dust.

Austin

Glad to hear it! I just put a whole day of service on my HD70 yesterday. What a great little machine.
post #22 of 25
Optoma Projectors are NOTORIOUS for color wheel issues.

The RPMs of the color wheel are monitored an if they drop below the accepted speed the projector will shut down. Since the lamp shines directly through the wheel the heat causes dust to gather on the assembly. This can lead to an imbalance of the wheel and eratic RPMs.

Keeping your projector clean and dust free is the best way to prevent this from happening. I think that many of the "defective" Optoma lamps I receive are actually victims of color wheel issues.

This goes for all Optoma's not just the HD70.
post #23 of 25
Quote:
Originally Posted by foranzi View Post

Optoma Projectors are NOTORIOUS for color wheel issues.

Oh please. Do your homework around here and read about the incidence of problems for all brands and leave your Optoma bashing for the kiddie forum elsewhere.
post #24 of 25
Just wondering what the best way to clean the HD 70 is because mine does the exct same thing.
post #25 of 25
I am having the same issues with my HD70. It will start to flicker and then gives an old atari type of beep noise then shuts down.

I have tried cleaning it out completely. That did work for a long while, probably 9 months. It then did the flicker again.
I then ordered a color wheel based on other posts with the flickering color but that did not fix the issue.
I then bought a new non-OEM fan thinking as the OP did that it was an overheating issue. The new fan would not spin at the correct RPMs (guess) so the projector shut down with the red light instead of the orange light. I then added the new fan in the correct place but wired it to the 12v plug located at the back of the projector and used the old fan in front of the bulb location on the outside of the case to track the RPMs. This worked and projected a picture for hours on end when it would only stay on for a few minutes previously. The only issue with this solution is that it is very noisy. I did order the OEM fan (70x70x20) thinking that just the correct new fan was all I needed but that is not the case. The color flicker is back with just the new OEM fan.
While I had it apart with just the new OEM fan in place and running as soon as it started to flicker I began to blow on the bulb with the additional fan and that would stop the flickering and continue to run.

So, in the end it seems as though it is overheating. I guess my question is, is it the bulb that has gone bad or is there a temperature sensor located in the same area that is being affected? I know about the temp sensor on the other side of the box but that is not close enough to be affected by this. I never got an end of life warning from the projector at any point but the bulb does have 1400 hours on it.

Any help is GREATLY appreciated.
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