hi there......as a stairlift engineer ,if a lift only goes one way the most common cause is safety edge d2d switch or wiring/loom..first tap all the safety edges on the side of the stairlift to see if any our stuck in....a common fault with the 250 models is the spade connectors wiring breaking in the skate housings due to movement on the rail tubing.move the stairlift to a place on the rail where you can work on it easier..
then remove the covers on the top skate and visualy look and test the wiring going to the d2d switches on the side the lift is not coming down on [sometimes the copper wiring can break inside the sleeving so look for kinks].repeat on bottom skate if not found fault on top skate.....another fault that can appear is, if you look at the back of carriage two looms one of each going to the top/bottom skates visualy look at the looms plastic sleeving these can split and cause wiring here to break if you are lucky enough put a call in on the stairlift and wiggle the wiring looms to see if lift moves otherwise test the wiring...let me know if this has helped...ian.....portsmouth/uk
IAN
January 2012