Hoover WindTunnel Model 5491-900 w/DirtFinder Indicator

[louvac]

Hey Guys!

I am baffled! I have the above mentioned model Hoover WindTunnel Model 5491-900. They're all the same basically just with plus or minus features. This one is kind of sharp since it has the "chrome" plate on the front nozzle. It's ice blue and does not have the power-drive feature.

Anyway....Though DirtFinder (red and green indicator lights) are working, they don't seem to be correct about whether the carpet is clean (green) or if there is still dirt (red) in the nap. Like all of you, since I vacuum more than the average person, the machine would be hard-pressed to find any real dirt in the carpet. This being said, what I discovered is if I put my hand in front of the headlight I can make the indicator lights go from red to green and vice-versa. How is this? Why is this?

I suspect that the "lens" wherever it is (which I thought was in the hose inlet area just before dirt enters the bag chamber) is dirty. IF THAT IS THE CASE, then why am I able to affect the indicator lights from going to green and back to red just by waving my hand in front of the headlight???

This is not a coincidence as I can do it every time! Is there some kind of "laser" in the headlight that can see dirt in the carpet? This just doesn't make any sense!

 

[loganvac]

From what I found,

this feature works just like a brush indicator light on a Kirby. The dirt that passes through the system physically "strikes" the sensor.

On the older Windunnels, the sensor should be right before the bag, but it's been years since I've serviced one of those. This small sensor is easily coated in gunk so you're right, it can only be so accurate.

Even if the sensors aren't coated in crud, Iv'e never believed they were accurate in gauging fine dirt pickup. Perhaps larger debris can be measured by this system more easily.

 

[loganvac]

As for you waving your hand in front of the sensor and it responding, that's certainly vexing because that would mean the sensor is light sensitive, but it shouldn't be because the sensor is enclosed and functions in complete darkness when in use.

 

[louvac]

Yes, this makes no sense!

This is what is perplexing! There is also a small hole a little smaller than a dime inside the headlight visor area opposite the headlight bulb. There is suction in this hole-again, this makes no sense to me, though I am not the engineer who designed this machine. I am sure there is a reason. Perhaps it's some sort of suction relief valve.

I am hoping some one else can shed some light on this-pardon the pun!