KWIRED, I think you hit the nail on the head. According to Liftmaster, this non-logic board design dates back to the early 2000's, and has not been made since then, so the fact that ours has a label showing date of mfg of Feb, 2019 likely means it was an old non-functioning unit that was refurbished on that date, but still an old design, and LIftmaster was quite emphatic about the non-authorized use of this outdoors and for rolling gates, which voided any warranty coverage we might have had. It's not hermetically sealed, just has a steel case cover over it, but that does nothing to protect if from the highly corrosive humidity and heat we have that has destroyed much electrical equipment over the almost 18 years we live here.
As I said in my most recent post, I, along with a knowledgeable tech (who at first couldn't believe we actually had this model...I had to send him a photo!), we spent two hours troubleshooting it and it appears the motor is dead...not burned from overload...it doesn't have that unique smell of burnt electrical equipment, so more likely a winding failed or some other part failed and not from overload. I have a fairly deep knowledge of electronics and electrical equipment...I can use an oscilloscope, signal generator, and various meters since I'm a kid and I understand exactly what tests we did, and even when we ran the line voltage directly into the motor there was no response. If that doesn't prove dead motor than I don't know what would. I also have a pretty deep understanding of our existing Tesla system, so electrical systems are not a mystery to me.
And your last sentence about the lower cost factor explains a lot....here in PR, many contractors will generally try to give you the cheapest solution, even if you ask for a good one. That's exactly what I meant by 'local engineering.' We intend to hold the seller's feet to the fire over this, and offer him the opportunity to either replace it with a proper unit, for which we will pay the difference, or just take it back and refund our money, or there will be more onerous consequences. We definitely do not want it repaired. We want it gone.
It appears NONE of the Liftmaster dealers here are aware of the use restrictions and non-warranty policy of Liftmaster regarding this usage. I've spoke to two different ones and neither mentioned this issue at any point...their response was 'we use this unit all the time,' which fits your analysis perfectly. That's their problem, not mine. Thanks for your input and I will post any solutions that surface.
