Re: Garage Door Opener sensors
I'm no tradesman, but here goes . . .
Chamberlain is the consumer brand; I bought one last in 2005 from Lowe's (assembled in Mexico). Liftmaster is the contractor brand (same manufacturer). Don't know if they differ in quality, but you can tell from which sales channel it was purchased.
If you can't get the exact manual via the web, try getting ANY Chamberlain manual (if able to, work back to around that time period). Look at the wiring panel diagrahms and see if they are common or follow some pattern. If the wiring is wrong, it just won't work and you won't fry the electrical or electronics. My guess is that the big difference is additional wire punches for additional wired controllers. The outside number controler is just another RF device so it won't need wire punches.
The RF controllers are different -- I have 3 Liftmasters and 2 are not compatable with the 3rd; I haven't tried looking for re-programming directions.
Also, hire a tech ??. . . you pays your money and takes your chances.
I just had a Yelp rated garage door guy replaced a broken lift spring. It was a hot day and charged me $340 (the spring was $80 next day delivery). I was a happy camper until the door wouldn't open 2 days later; he quickly came back and made a 2nd fix while my wife was at home. The fix was good until a week later I noticed one edge of the door is now 1-2" above the ground when closed (critters can party in my garage). WTF.
On the 3 Liftmasters in my current house (being Liftmasters, they were contractor installed, and built around 2000-04), the installers attached the sensor eyes to the motor case - - it appears the SOB's didn't want to run the obstruction sensor wires to the door frame bottoms, and they probably couldn't bypass the sensors by jump wiring, so they had them pointed to each other on the motor housing case. WTF. The old lady who lived there until 2004 wouldn't know the difference .. . or so they thought.
Last edited by t_manero; 09-05-2012 at 10:38 AM.