I have an older , Sears, chain operated garage door opener. Mechanically,
the door is working fine, but I have a problem with the two safety sensors
that beam a light across the bottom edge of the door, about 5 inches off the
floor bottom.

The door will open fine, but will not close. I am 99% sure the problem is
in the two sensors just described.

On one of the sensors, which I think is the sending unit, the little pilot
led light is bright and pretty. However, on the other unit, which is
marked the "Receptor" unit, the small led light is barely, barely, lit.
It is getting voltage, as the led pilot light will very faintly light up
when I apply the electrical wiring plug into it. I can also tell that when
I line up the two sensors, and then place my hand across the beam of light,
I can just barely detect that it faintly changes the intensity of the led
pilot light.

My suspicion is that this "Receptor" unit has gone bad.

Two Questions please:

1. Am I on the right track ?

2. Can these sensors be bought at Lowe's or Home Depot ?

---------------

Any comments or input would be very much appreciated.

Thank you very much !!

James

On Jan 16, 2:27*pm, "James" wrote:
I have an older , Sears, chain operated *garage door opener. *Mechanically,
the door is working fine, but I have a problem with the two safety sensors
that beam a light across the bottom edge of the door, about 5 inches off the
floor bottom.

The door will *open fine, but will not close. *I am 99% *sure the problem is
in the two sensors just described.

....
Two Questions please:
1. *Am I on the right track ?

Possibly...take them and place directly in front of each other a foot
or so apart and test -- if works reliably, pretty good clue. Of
course, make sure the lenses are clean on both. Also can test by
jumpering the input to close the circuit to test.

2. Can these sensors be bought at *Lowe's or Home Depot ?
....
I'm sure somewhere they can be obtained; whether at the BORG's I don't
know; all my openers are old enough they predate the infrared sensors
so never had any need for replacements...

--

My suspicion is that this "Receptor" unit has gone bad.

The lens on either unit might need cleaning. Sometimes sunlight
during the evening or morning will hinder their operation.

Ok, I shorted the wires going to the Receptor Sensor, and when I do that,
the small led light on the Sending unit goes out, but the door will still
not go down. The only way that I can make it go down is to press **and
hold** the manual switch inside the garage itself. I assume that by
doing this, I am in effect, manually by-passing the safety
feature...........

It will go up fine.

Any other ideas ??

James

On Jan 16, 3:19*pm, "James" wrote:
Ok, *I shorted the wires going to the Receptor Sensor, and when I do that,
the small *led light on the Sending unit goes out, but the door will still
not go down. * The only way that I can make it go down is to press * **and
hold** *the manual switch inside the garage itself. * *I assume that by
doing this, I am in effect, *manually by-passing the safety
feature...........

*It will go up fine.

Any other ideas *??

As noted, never had one w/ the light interlock to have had the
opportunity to fiddle w/ it, but would seem that would be wrong set of
leads to short -- I'd think there would be a completed circuit via the
emitter/sender unit from one to the other. The inputs at the unit
from the interlock would be where I'd do my jumpering...again, this is
surmising w/o direct experience.

Did you try the lens-cleaning and the direct-coupling alignment/
sensitivity experiment(s) suggested?

--

dpb:

Did you try the lens-cleaning and the direct-coupling alignment/
sensitivity experiment(s) suggested?

------------------

I am going to do this experiment tomorrow. Thanks !!

G. Morgan, you link to the Amazon site is great !! If it looks like I need
the sensors, that will be my ready source !!

Thanks to both of you !!

James

Ok, I did try the "free wheel" test, by releasing the latch and manually
putting the door up and down. It goes up and down freely, with no binding
etc

I tried to do the eye to eye matchup with the two sensors, but when I plug
the receiver sensor in, the led on the transmitter goes out. This is not
right........

if i just keep power to the transmitter, the led comes on.......... but
when I power the receiveer, the transmitter light stays on, no matter where
i aim the receiver.... there is just no pilot light on the sending
unit........

from this, I am suspecting more and more that I have bad sensors.....

what you guys think ??

James

in that last message, I typed one word wrong..........

here is the correct paragraph........

-------------
if i just keep power to the transmitter, the led comes on.......... but
when I power the receiver, the transmitter light stays OFF, no matter where
i aim the receiver.... there is just no pilot light on the sending
unit, as long as I have power to the receiver........