We have Otis Service Tool, we have diagrams for this equipment, we have manuals control and drive unit Model OVF-30, its a DC drive with SCR and a DC motor.
We have check the hoistway vanes, the inductors over the cabin, gone thru the manual. And this has been frustrating.
Lately we found out that the elevator was not balanced, apparently somebody took some weights from that elevator to use them in another one. After we installed the weight on the counterweight was needed to balance the elevator (Static Balance). The elevator commenced to work perfectly well for 2 days and then he go back to the same thing. Then we put apprx 276lbs of weight on the top of the cabin that we too of from the counterweight and is working better but eventually do the same thing. WE do the shaft learning with the Service Tool and works ok for a while. We need someone very knowledgeable of this kind of equipment to assist us solving this problem. You help will be appreciated and remunerated if needed. Wait for your reply. Thanks.
Smaller companies love to bash the big boys for trying to "take advantage" of customers but this is what the majors have to think about. I have had multiple instances of this type of situation happening. One of them seriously injured a passenger which resulted in a huge lawsuit. If you don't know what you are doing please don't put the public at risk, it's bad for the whole industry.
Dan Zeitz was kind enough to post "Jumpers--Mechanic goes to jail" in print talk. The article explains that the mechanic was charged and prosecuted for his actions while working on an elevator. The choice not to secure control of the elevator before bypassing any part of the safety circuit is a bad choice. Bypassing the entire safety circuit was in this example CATASTROPHIC!
So with every repair you may want to ask yourself, How far do you think a Lawer will go to point the finger of blame at the mechanic(s) who have worked on this elevator?
With all the information I have to form an opinion, It is my opinion that if the controller (as you claimed) completely went on fire, replace it. How much money could you have saved the customer? And like you said "the elevator runs almost perfect". If the customer is tight with their money, ALMOST PERFECT will haunt you for some time.
And if for some reason you find yourself in court! Don't forget to mention "the elevator was running ALMOST PERFECT"!