Home Forums General Discussion Technical Questions Dover 4slot

I have had a repeat call Dover 4slot from 1972 in an apartment complex elevator faults out sometime over night and when they call it in it is sitting on buffer springs. Once you reset it runs with no issues it may run a day or week then randomly faults out again over night I have reseated and cleaned cards. Replaced both capacitors TL and C1. Any thoughts on what may be causing this intermittent problem. I have verified voltage on my power board at 5.1VDC when its faulted any thoughts would be very much appreciated

The valve leaks so that is why it ends up on the springs I also checked the relevel circuit and it does relevel on all floors

Check the lom pin on the power card to 0 volts when normal. If that changes when faulted then its on low oil. What type of valve?

I2 or P125 valve?

The valve has been changed out to a Maxton valve several years ago

Check the valve fir sizing. If wasn't sized properly it will fault out on low oil when the unit calls for heating cold oil.

hey I have a 3 stop 4 slot dover giving me fits and I dont have a complete set of prints- it will always stop at middle floor regardless if button is pushed in up and down- it also will sort of go to sleep when at the bottom floor and wont respond to anything-changed mid floor card and no change