When I bypass the contact switch on my outside unit the unit comes on. Why will it not work without being bypassed. Also the unit stays on because of the bypass unless I turn off the disconnect on the wall by outside unit.

By your description I would think that the contact switch is bad. Have you tested it to see if it makes and breaks contact.

I would replace the switch

Chuck

What switch are you bypassing? The outside contactor requires 24 volts to the contactor.