Thanks for the replies. It's a Sears Craftsman, 1/3 HP. Maybe about 100 yrs old!! It does also have the pressure switch and the sun does hit one "laser" sensor or the other depending on time of day. BUT,it happens at night and in any kind of weather, usually for several days or weeks at a time in either mode, working or not.
Now, I'm not sure how to wire both sensors together. I'd go for that in a heartbeat and expect it would cure the problem. Somebody give me a simple schematic? There's only one pair to each sensor, it can't be that hard and I do have a voltmeter.
Thanks,
Bob
Sears Craftsman, 1/3 HP. Maybe about 100 yrs old!!
When it acts up does the light bulb blink on and off(or click if bulb is burnt out)? Blinking about 8 times is a signal something is wrong with the eyes.
If it's a hundred years old and has photo eyes then they are the type with a thru bolt holding them to the bracket. For the first couple years since '92 Chamberlin(makers of craftsman) had a really crappy design that involved the wires using plug connectors on the backs of the photo eyes. Very common point of trouble, check that first. If you can wiggle the wire coming into the photo eye and make the led light flicker then clean those little pins inside the photo eye, and spread them slightly so the plug holds on tight. If the wire goes directly into the photo eye then go to..
Next step, check the wire connections on the head unit.
Next, check that your door works smoothly by hand and is balanced. If it is check the sensitivities(little knobs on head labeled 1-9). On a properly adjusted door they should be set at about 5 or 6. Sometimes if set to low that can cause intermittent problems(will not cause light to blink).
If still no joy then I'm afraid you most likely have a logic board problem, or possibly the photo eyes themselves(sending unit also has a board inside). At this point, I'd try a new set of eyes or logic board, or I'd just sell you a new one.
As far as wiring the photo eyes for a chamberlin, on both eyes wire with the stripe goes to terminal 3(black) on the head and white wire goes to terminal 2(white). It won't hurt it if you get it backwards it just won't work.
If it really is toast, you can get a dual lamp 1/2 hp Craftsman refurb from Sears, complete with two remotes and a door pad, for under $175. Install it yourself in about two hours.
I'm sure yours turned out great but you have no idea how much money I make repairing operators the home owner "just replaced" cause he didn't take care or notice a bigger problem and screwed his new op up.
I'll admit I'm probably biased, but the crap you will buy from any hardware store is exactly that, crap. Take your $175 or so and go to your local garage door dealer and buy an op from him carry out. Buy something with a solid 1pc T rail and a full chain for roughly the same price. Stick with Chamberlin, they make about a million different brands but most 90% of the parts are interchangable. Makes for cheaper repairs down the road.
