View Full Version : lennox unit

16-06-2009, 05:08 PM
Hi guys
I have a Lennox LGK075-H-2M, the pressure differential switch has disintegrated and I canít get one like yesterday, does anyone know if I can by- pass the switch temporarily to help the customer, this switch tells the unit whether the fan has failed or filters have blocked, etc, it connects to the KP01 board, 18 volt output, I need to know if we can do this safely without damaging the PCB board.

The Viking
16-06-2009, 06:00 PM
Is there a reason why it can't be an universal one?

RS does several different versions.

16-06-2009, 06:09 PM
there are re openeing tomorro!!

Yuri B.
16-06-2009, 06:35 PM
It seems it is not PCB which may be damaged. Supposing "LGK075-H-2M" is some induct AC? - I probably would make the bypass if I were you (if all is clear and works smoothely). Only, maybe, add a NO contact relay (instead of the diff relay) switched parallel with the fan so that controller knows that at least voltage to the fan goes?